If Clemson QB Deshaun Watson plays the whole season, that might decide the ACC

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A 6’1, 177-pound walk-on from Pelham, Ala., Dabo Swinney earned a scholarship at Alabama and caught seven passes for 81 yards in three years. In his junior and senior seasons, Alabama went 24-1, finished in the top five twice, won the first SEC title game, and whipped Miami for the 1992 national title, and he carved out an unexpected niche.

Not even two decades later, he found another unexpected role: Clemson head coach. Swinney had spent three seasons as a Bama grad assistant and five as a position coach, but when head coach Mike DuBose was fired after the 2000 season, he ended up spending two years with a friend’s real estate company. Tommy Bowden, his receivers coach when he was a freshman, convinced him to rejoin football in 2003.

Clemson came to value his recruiting ability so much that, when Bowden resigned halfway through 2008, Swinney was named interim despite having never served as a coordinator. And when he went 4-3, whipped South Carolina, and put together the pieces of a great recruiting class, he got the job full-time.

There is infinite value in understanding your limitations. Swinney has been proving that for almost 25 years. With no experience, Swinney rode his strengths to a huge job, and he is thriving into his seventh season. Lord knows recruiting has played into that, but so has another strength: hiring assistants. He’s nailed the most important tasks.

From 2008-10, Clemson’s offense struggled more than it should have. With players like C.J. Spiller and James Davis in the backfield, Clemson ranked 79th, 41st, and 71st in Off. S&P+ and went 19-18. In need of a spruced-up offense to save his job, Swinney brought in Chad Morris, a renowned spread guru who had spent only one year in the college ranks. After 16 years as a high school coach in Texas, he’d spent a season with Todd Graham (another high school-to-college guy) at Tulsa and improved the Golden Hurricane’s Off. S&P+ rating from 71st to 15th. Combined with strong recruiting, the results were instantaneous: 25th in Off. S&P+ in 2011, 14th in 2012, 12th in 2013.

Meanwhile, defense spiraled. The Tigers fell from sixth to 65th in Def. S&P+ in 2011, marring what was still a 10-win season. In need of a replacement for coordinator Kevin Steele, Swinney landed longtime Oklahoma coordinator Brent Venables. The improvement was slower but no less sure: 62nd in 2012, 41st in 2013 ... and second in 2014.

Clemson has won at least 10 games for four consecutive years and pulled off three consecutive top-15 poll finishes for the first time since 1988-90. Swinney’s allowed the program to blossom into what Clemson fans think it should always be.

And now comes the next test: replacing Morris. The 46-year-old moved back to Texas to take the SMU job, and Swinney stayed in house to find his replacements. Receivers coach Jeff Scott (who took over as Clemson’s ace recruiter when Swinney got promoted) and running backs coach Tony Elliott (whom Swinney brought in after 2010) are now co-coordinators. The Tigers need a little bit of offensive redemption -- turnover, injuries, and a suddenly awful running game led to some impressive slippage in 2014 -- but after back-to-back home run hires, Swinney gets the benefit of the doubt.

Assume Swinney’s biggest decisions will work, until proved otherwise.

Clemson’s 2014 season was one of ill timing. Thanks in part to one of the most dominant lines in college football, the defense peaked just in time for the offense to crater. A team with Clemson’s 2013 offense and 2014 defense would have ranked third in overall S&P+ last year, but instead the Tigers slipped from 16th to 17th.

But coming up with any sort of full-season conclusion for Clemson is pointless, as the team’s makeup changed frequently. Freshman quarterback Deshaun Watson overtook veteran Cole Stoudt in the starting lineup, got hurt, came back, and got hurt again. With Watson, Clemson was a bit inconsistent but infinitely more explosive. Without him, it was directionless.

An encouraging mini-trend formed at the end. Clemson played at the 93rd percentile or higher in five games last fall, including the last three games. Watson led the way against South Carolina, but the team was just as dominant without him against Georgia State and Oklahoma.

If three games is a trend, Clemson might be in good shape. The problem: defense led the way in those three games. The offense averaged 8.1 yards per play against South Carolina but only 4.8 against GSU and OU, whereas the defense allowed 3.7 yards per play in the three contests. But the defense has been wrecked by graduation and attrition, meaning the offense will have to carry far more weight.

Note: players in bold below are 2015 returnees. Players in italics are questionable with injury/suspension.

Motion to allow Watson to wear a purple “no tackling allowed” practice jersey all year.

Watson’s 2014 was teased potential. He broke his collarbone, broke his hand, and injured his knee. In limited time, he proved the recruiting rankings right, putting up explosive passing and efficient rushing. He won the starting job by helping to nearly defeat Florida State, led two of the season’s best efforts (against UNC and NC State), and completed 14 of 19 for 269 yards against South Carolina on an injured knee.

Watson suffered so many injuries that he will have an “injury-prone” label even if he doesn’t any more time.

And that would have been fine had Stoudt been a strong option, but he wasn’t. His completion rate was decent, but there was no downfield threat; whereas Watson averaged 15.8 yards per completion, Stoudt averaged 9.9. And while his career finished with a great performance against Oklahoma (26-for-36, 319 yards, 3 TD, 0 INT), he was 19-for-40 for 163 yards, no scores, and four picks in losses to Georgia and Georgia Tech. Bad Cole was really bad.

In 2015, it’s all about Watson. With him, Clemson likely has a top-30 or top-40 offense even if the running game doesn’t improve. Without him, former walk-on Nick Schuessler is the likely starter. The supporting cast will need to raise its game -- even with Watson, the run game stunk -- but it will be an outright necessity if Watson misses time.

Former starting quarterback Tajh Boyd, an efficient runner, was gone, and while Watson was equally efficient, Stoudt was not. Plus, CU replaced steady Roderick McDowell with basically three freshmen (Wayne Gallman, Adam Choice, Tyshon Dye) and a walk-on track star (C.J. Davidson). Plus, the Tigers had to replace three starting linemen.

Regression would have been understandable. Clemson plummeted. In 2013, the Tigers ranked 32nd in Rushing S&P+ and 21st in Adj. Line Yards; in 2014, they ranked 107th and 101st. Stoudt was asked to throw far too many second- or third-and-long passes. Almost nobody’s going to look particularly good on those downs.

Whether the QB is Watson or Schuessler, experience must lead to improvement. Gallman, Davidson, Choice, and Dye are back, as is junior Zac Brooks, who missed 2014 with a foot injury.

Of course, there’s more turnover up front. Clemson does return four senior linemen who have combined for 43 career starts (unless there are legs to the current “Isaiah Battle kicked off the team” rumors, in which case that number falls to 28 [Update: Battle’s gone to the NFL Supplemental Draft]), but three more starters are gone. That leaves the veterans and some blue-chip youngsters (freshmen Mitch Hyatt and Jake Fruhmorgen, sophomore Tyrone Crowder) to create a happy mix.

I think last year’s regression was so steep that there will be a bit of a rebound, especially when Watson is healthy. But the line could prevent any significant improvement.

If the run game can improve to mediocre, man oh man, does the passing game have potential. In four games with Watson as the primary, Mike Williams caught 17 passes for 408 yards (24 per catch) with four touchdowns; in those same games, Germone Hopper caught six passes for 219 yards and two scores.

Artavis Scott, meanwhile, went from efficiency target (83 percent catch rate!) to all-around terror late in his freshman year, catching 15 balls for 299 yards and three scores against South Carolina and Oklahoma.

Oh yeah, and not only do four-star redshirt freshmen Trevion Thompson and tight end Milan Richard both enter the rotation, so do five-star blue-chippers Deon Cain and Ray Ray McCloud.

Few, if any, teams have recruited better at receiver than Clemson. There was too much youth, and too little help from the run game, for Clemson to be efficient throwing the ball, but experience should work wonders.

Before talking about Clemson’s 2015 defense, let’s take a moment to eulogize an incredible 2014 unit. We knew heading into the season that the line was one of the country’s best, and it lived up to billing, but despite losing nickel back Travis Blanks, the secondary broke through significantly. The Tigers’ efficiency was still top-notch (fifth in Success Rate+ in 2013, first in 2014), but big gains were impossible to find; Clemson went from 107th in IsoPPP+ to second.

The result was a nearly unimpeachable defense. Of the 26 advanced rankings listed above, Clemson ranked in the single digits in 24. One of Clemson’s two lesser ratings (advanced field position) was due to an abysmal return game, and the other (Fourth Quarter S&P+) involved inconsequential garbage time possessions. Georgia, Georgia Tech, and UNC averaged 36 points per game and 6.2 yards per play; the other 10 teams averaged 3.3.

Good recruiting means Venables still has plenty of talent to work with, but we’re not going to see the same this year. Clemson must replace six of last year’s top seven linemen, its top two linebackers, and its most productive safety and cornerback. The back seven should be solid, but the line is starting over.

Recruiting and continuity have been so strong that, while Clemson is tasked with replacing more line production than anybody else in the country, the Tigers still return three interesting juniors (ends Kevin Dodd and Martin Aiken, tackle Carlos Watkins) and a senior (big tackle D.J. Reader) with decent experience. These four seem to have playmaking potential -- they combined for just 27.5 tackles in 2014, but 8.5 were behind the line. Including DT-turned-OL-turned-DT Roderick Byers, Clemson’s got plenty of veteran options. Regression is inevitable, but experience should assure a high floor.

Blue-chippers hint at a high ceiling, too. Four-star sophomore end Scott Pagano could play a role, but it’s hard to keep your eyes off of the incoming freshmen. Between tackles Christian Wilkins and Albert Huggins and ends Clelin Ferrell and Austin Bryant, one assumes at least one or two will be featured in this year’s rotation.

The linebacking corps is stocked with a combination of known quantities (junior Ben Boulware, nickelback/OLB Korrin Wiggins, maybe B.J. Goodson) and crazy-upside youngsters (Dorian O’Daniel, Korie Rogers, Chad Smith). [Update: Rogers left the team in August.]

There’s raw talent. How much is coaxed out will determine whether Clemson’s D regresses a little or a lot.

Thanks to the return of Shaq Lawson, Clemson’s defensive end situation is probably more stable than its tackle situation. (Honestly, the loss of active tackle Grady Jarrett might hurt more than losing all-world end Vic Beasley.) The run defense will slide, but if the pass rush is solid, the secondary should return more than enough to continue doing damage.

Safety Jayron Kearse is one of the best back-line playmakers in a conference full of them, and blue-chipper Mackensie Alexander did well as a freshman. The return of senior Travis Blanks gives Venables creative options, and junior safety Jadar Johnson made plays in limited opportunities.

Venables spends a lot of time in the nickel set, and considering the strength and weakness of the personnel, he might spend even more this year. Big safeties like Blanks, Johnson, and T.J. Green give Venables flexibility, and the smaller Korrin Wiggins is on his way to mastering the art of the nickel back.

As many worries as there are up front, there are few in the back.

In order, Clemson’s special teams strengths last year were punter Bradley Pinion and kicker Ammon Lakip. Lakip missed a few shorter field goals, but he made over half of his longer field goals, which accounted for deficiencies.

Pinion has graduated, and as this piece goes live, Lakip is facing cocaine and DUI charges. To say the least, his status is uncertain.

That leaves Clemson with a shaky coverage unit and non-existent return game. There’s no excuse for a team this deep at receiver and defensive back to have coverage problems, and surely one of the incoming youngsters will be capable of providing a boost in the return game, but at this point, Clemson’s special teams is a significant weakness.

At the end of each set of conference previews, I release a set of tier-based power rankings. I usually try to avoid putting too much emphasis on quarterback, but it’s impossible when Clemson is involved. When I rank the ACC, I’m tempted to list two Clemsons, one that features the best QB in the league and one that doesn’t.

With a healthy Watson, a lot of potential weaknesses get covered up. The running game has an extra efficiency option (and if the defense is going to regress in run defense, ball control and efficiency become doubly important), and the passing game has an absurdly high ceiling. Line play is a concern no matter what, but Watson appears good enough to drag Clemson toward a strong season.

But what if Watson gets hurt again? His injuries were disparate enough that we shouldn’t assume he will always have issues, but until he proves he can survive for a whole season, we don’t know. And without Watson, either a former walk-on or a true freshman (one less touted than Watson) takes over, and all of the offense’s potential weaknesses play marquee roles.

With Watson, Clemson is a Tier 1 team in the ACC. Without Watson, Clemson might fall behind Florida State, Louisville, Virginia Tech, and Miami at least.

With Watson, the schedule sets up beautifully. Clemson faces three projected top-20 teams, but all three come to Death Valley, and while trips to Louisville, Miami, South Carolina, and perhaps NC State could be quite tricky, Clemson could be favored in every game. Without Watson, 6-6 is on the table.