Louisville football’s going to be volatile, dangerous, and all sorts of fun in 2016

Check out the advanced-stats glossary here. Below, a unique review of last year’s team, a unit-by-unit breakdown of this year’s roster, the full 2016 schedule with win projections for each game, and more.

Not going to lie: I was having doubts. When a coach with the points-happy reputation of Bobby Petrino starts a new job, you just assume it’s only going to take him so long to figure things out. That’s his track record.

At Louisville the second (third?) time around, however, we seeing a different trend. After averaging 35.2 points per game in Charlie Strong’s last year, the Cardinals lost a ton of production (quarterback Teddy Bridgewater, for starters), alternated between freshmen and a sophomore at QB, and fell to 31.2.

Eight games into 2015, UL was averaging only 24.4. Petrino was still shuffling quarterbacks like crazy, his offense had no flow, and his newfound fascination with mobile QBs didn’t mesh with what he had typically done. I wondered about the future of the Petrino offense and how long it was going to take.

And then the last five games happened.

The offense surged just in time for the defense to regress a bit, but wow, did the offense surge. First, sophomore quarterback Kyle Bolin torched Syracuse for 362 yards passing and three touchdowns in a 41-17 win that included a 34-0 UL run. Then, as Bolin struggled against Virginia, running back Brandon Radcliff ripped off 146 rushing yards and two scores to lead the Cardinals to a 38-31 shootout win.

Then, freshman Lamar Jackson took over. He entered the Pitt game late in the second quarter, with Louisville down 42-17. He led three scoring drives to get the Cardinals within 42-34 before the Panthers put the game away with a field goal. The next week, Bolin threw two early interceptions as UL fell behind Kentucky, 21-0. Behind Jackson, the Cardinals tied the game in the third quarter and won it in the fourth.

The Music City Bowl served as a coronation of sorts. Jackson played the whole game, threw for 227 yards, and rushed for 226. His 61-yard touchdown run put Louisville up 20-7 at the end of the first quarter, and his second touchdown pass all but put the game away in the third.

The Louisville offense suddenly went from young and flawed to young and volatile, capable of explosive bursts to offset inexperience. And those bursts were a) incredible and b) mostly due to Jackson.

And now the Cardinals return almost literally everybody: both Jackson and Bolin at quarterback, the top three running backs, basically every receiving target, five offensive linemen with starting experience, four of the top six defensive linemen, four of the top six linebackers, and six of the top seven defensive backs. There might be some depth issues on the lines, and the QB position is destined to go through a few more growing pains here and there, but we saw the upside. Now we get to find out if Petrino and the Cardinals can maintain it.

This is Bill C’s daily preview series, working its way through every 2016 team. Catch up on the ACC so far!

Late-season surges can be meaningful if the reasons for the surge return. If your level improves over a period of three or four or five games, and those responsible for the improvement are back in uniform the next fall, the small sample can really be a sign.

There are two questions:

1. How do we define this surge? UL clearly became more explosive over the final five games, but half of that was due to Bolin, and half was due to Jackson covering for Bolin.

2. How worried should we be about a defense that faded while the offense was clicking? Granted, a good portion of opponents’ late-season points came from offensive mistakes, but ... in that case ... should we be more worried about offensive volatility than we are?

Because of the mistakes, Louisville still lost a game during this late-season surge and could have lost three more. Because of upside, the Cardinals did not. I completely understand why S&P+ has boosted UL to 20th in the 2016 projections, and the upside here is tempting. But even during late-season improvement, the warts were obvious.

Note: players in bold below are 2016 returnees. Players in italics are questionable with injury/suspension.

The highlights are eight steps beyond seductive.

Upside, upside, upside. It’s impossible not to use the word. He didn’t finalize his starting role until the bowl game, he was part of plenty of iffy performances, his INT and fumble rates were a little bit high, and his sack rate was far too high. But he still threw for 1,840 yards, and before factoring in sacks, he still rushed for 1,143. If that’s the unvarnished version ... goodness.

If Jackson ends up Louisville’s primary quarterback all year (meaning, if he stays healthy and doesn’t fall into a slump), he should pass 2,500 passing yards and 1,500 rushing yards. That’s incredible in and of itself. The question is, how many glitches will we see? How many lapses of inefficiency will we see between the bursts?

Even as Jackson won the starting job, he completed just 45 percent of his passes in the final three games. His legs are amazing, but some of the opponents on the 2016 slate will slow his rushing a bit. His mastery of the Petrino passing system will be vital.

Jackson’s legs would make just about any run game efficient. Louisville ranked 21st in Rushing S&P+ despite his occasional absences and despite the fact that Louisville running backs had an unimpressive opportunity rate (percentage of carries gaining five yards) of 32.2 percent.

To prevent Jackson from taking a 13-game beating, Brandon Radcliff and company will need to become more consistent. Radcliff averaged 4 yards per carry over the first eight games of the year, erupted for 263 yards on 31 carries (8.5) against Syracuse and Virginia, then averaged 3.4 the rest of the way. L.J. Scott did contribute 83 yards in nine carries over the last two games, but the run game was all on Jackson, and that is grueling.

Still, the experience bleeds into the receiving corps, a dynamic mix of seniors, sophomores, and an exciting former quarterback.

The seniors: James Quick, UAB transfer Jamari Staples, and tight ends Cole Hikutini and Keith Towbridge were dynamite in 2015, especially considering the constant turnover at QB. Quick and Staples were massive big-play threats, averaging 16.6 yards per catch and 9.9 yards per target over 10 targets per game. The tight ends topped them: 17.3 yards per catch, 12 yards per target.

The sophomores: Jaylen Smith, Traveon Samuel, Devontee Peete, and tight end Micky Crum combined for 74 catches in their debut seasons, which is certainly exciting moving forward. As Jackson continues to develop, he will have plenty of familiar faces around him in the coming years. Still, this foursome combined to only average 6.6 yards per target with a 43 percent success rate. That’s only borderline effective, even for freshmen.

The former quarterback: Despite all of this returning depth, Reggie Bonnafon could end up starting at receiver. As a QB, he was too inefficient and sack-prone, but his athleticism and potential efficiency were obvious. He emerged as a decent possession receiver in the middle of the season, and if the running backs are still struggling from an efficiency standpoint, Jackson could come to lean on Bonnafon to generate steady, quick gains.

Petrino signed a foursome of exciting incoming freshmen as well, including 247 four-star Dez Fitzpatrick. It will be impossible to get everybody the touches they deserve, but that’s the kind of problem you like having.

The line was crazy-young -- as you see, of the five returnees with starting experience, four were freshmen and sophomores. And young linemen already have enough to keep track of without trying to block for the moving target that is Jackson.

Quarterbacks like Jackson struggle with sacks, both because they trust their legs too much and because it’s hard to block for a guy who could dart anywhere at any time. Consequently, the Cardinals had one of the worst Adj. Sack Rates in the country.

Jackson can also make you look good in run blocking. Despite a woeful stuff rate, UL ranked 18th in Adj. Line Yards. And considering the inefficiency at RB, it’s clear that Jackson played a major role there, too.

Depth up front took a major hit with the departure of a few backups, so if the projected starting five loses a couple of players to injury, the line could quickly end up as inexperienced as it was last year. But starting out, the starting five should be solid. Less glitchy, anyway.

Louisville’s 2015 defense was a science experiment; the Cardinals had to replace half their starting linebackers and each of their top five defensive backs from the year before, and they did so with three key transfers: TCU’s Devonte Fields and Georgia’s Josh Harvey-Clemons and Shaq Wiggins.

The result: survival. The run defense was every bit as good as it had been in 2014, and the redzone defense held steady. But as continuity in the secondary is vital, the pass defense still regressed (from 20th in Passing S&P+ to 51st) despite the high-upside newbies.

Coordinator Todd Grantham still put a top-25 defense on the field, though, and considering the turnover, that was a nice hurdle to clear. Louisville ranked 24th in Def. S&P+ a year after ranking 14th. And while the depth has been skimmed again, there are enough pieces to assume another top-30 defense is likely.

The calling card for Grantham is aggressiveness. No bend-don’t-break here. Louisville ranked 13th in havoc rate, and 36 percent of opponents’ incompletions were due to passes defensed (interceptions or pass break-ups), 38th in the country. Despite some breakdowns in the back, Louisville still attacked the opponent well, especially before the slight late-season fade.

Louisville generated more havoc than just about anybody in the country from the linebacker position: the Cardinals’ 9 percent havoc rate from LBs ranked third in the country, actually.

The primary source of disruption were pretty obvious. Fields took complete advantage of his second chance by racking up 22.5 tackles for loss and 11 sacks as a junior, and the fact that he’s staying for his senior season is a massive victory for Petrino and Grantham. With him distracting blockers on one side, that frees up other attacking options, from fellow OLB Trevon Young to middle man Keith Kelsey, to whichever defensive end steps up to replace the production of Sheldon Rankins.

That Rankins, Pio Vatuvei, and Nick Dawson-Brents are all gone means the end position is going to be pretty green and thin, but junior James Hearns has shown solid potential while oscillating between lineman and linebacker. And getting Johnny Richardson back healthy will help.

Returning three linebackers who combined for 44.5 tackles for loss is an incredible luxury. This front seven will look drastically different in 2017 considering the senior contributors, but we’ll worry about that in 2017.

Despite a solid pass rush, Louisville indeed struggled to defend the pass at times, and this contributed quite a bit to the win-loss totals. In wins, the Cardinals allowed a 105.3 passer rating; in losses, 147.2.

The problems came primarily on third down, and not only on third-and-short. On third-and-four or more, opponents were allowed to complete 52 percent of their passes (not bad) at 15.2 yards per completion (not good) with only three picks. Louisville did a good job of forcing passing downs but couldn’t get off the field once the opponent was leveraged.

Again, the struggles were predictable considering the turnover. The Cardinal secondary was brand new, stocked not only with transfers, but with quite a few freshmen and sophomores. And most of them are back.

Continuity should aid in balancing risk with reward. Louisville returns two safeties (Harvey-Clemons, Chucky Williams) who combined for four TFLs and 16 passes defensed and two corners (Wiggins, Trumaine Washington) who combined for 7.5 and 23, respectively. The play-making potential is there, and sophomores like potential first-string nickel back Dee Smith and Jaire Alexander and JUCOs London Iakopo and Ronald Walker can only help. I would be surprised if this pass defense didn’t improve into at least the 30s in Passing S&P+, maybe the teens or 20s.

Continuity is an obvious strength for both the offense and defense, but special teams takes a hit. There are some exciting sophomores in the return game who showed explosiveness through inconsistency last year. But John Wallace, a decent strong kickoffs guy and decent place-kicker is gone, as is one of the best high-ball punters in college football Josh Appleby averaged barely 40 yards per punt but almost never gave up a return. That is an underrated skill.

S&P+ says Louisville has at least a 64 percent chance of winning in each of its last seven games; that should allow for the Cardinals’ win total to creep toward nine games and establish them as the ACC’s third-best team (while in the same division as the two ahead of them).

If they want to make something more of 2015, however, it will happen early. UL hosts Florida State in Week 3, and S&P+ gives the Cardinals a nearly 50-50 chance of pulling off a big win. Winning at Clemson is less likely, but if you beat FSU and start 4-0 (which will require tricky road wins at Syracuse and Marshall, too), you’ll be stealing a lot of headlines and opening up the possibility of a three-way ACC Atlantic tie.

I’m guessing that probably doesn’t happen; I figure Jackson still has some lapses to work through, and they’re more likely to happen early. But even with potential inconsistency, the upside should show itself enough to make the Cardinals one of the more dangerous teams in the country.