2013 NFL Rookie of the Year watch, Week 8: Zac Stacy makes his mark against Seahawks

It took a while, but Zac Stacy finally broke free.

Starting the season behind Daryl Richardson and Isaiah Pead, the outlook on Stacy's rookie season looked bleak. Injuries and off-the-field issues helped Stacy get his chance a few weeks ago, and he hasn't looked back. The former Vanderbilt running back had his most impressive outing of the season against the Seattle Seahawks, rushing for 130 yards on Monday Night Football.

Zac Stacy Running Back, St. Louis Rams: Stacy had his best statistical game of the season on Monday night, but he may have been more impressive than the numbers indicate. Consider the fact that the Rams were playing with Kellen Clemons under center with Sam Bradford out for the season. St. Louis had no semblance of a passing game, but Stacy was still able to churn out tough yards against one of the league's best defenses. He suffered an ankle sprain at the end of the game, but hopefully he's able to stay healthy to build off his strong game.

Tyrann Mathieu, Defensive Back, Cardinals: Tyrann Mathieu has been mentioned in this space before, but his performance on Sunday is worthy of inclusion again. In an Arizona win, Mathieu showed off his versatility, covering receivers in the slot and also playing as a safety over the top. He's a valuable piece of an improving Cardinals defense and has been one of the best rookies this season.

Datone Jones, Defensive End, Green Bay Packers: Datone Jones has been eased into action for the Green Bay Packers, despite being a first-round pick. So it's not a huge surprise that he's been quiet as a rookie. However, against the Vikings in Week 8, Jones was disruptive in the running game and seems to be working his way into the Packers' rotation on defense.

Geno Smith, Quarterback, New York Jets: Inconsistency is an issue for most rookie quarterbacks, but Geno Smith is taking it to a new level. He's been solid for the Jets at times this season, but games like Sunday's blowout loss to the Bengals leave fans scratching their heads. He turned the ball over twice more on Monday and was pulled from the game. He's not really in the running for Rookie of the Year at this point.

Jamie Collins, Outside Linebacker, New England Patriots: Still playing in a situational role, New England Patriots pass rusher Jamie Collins has struggled to get into the backfield so far this season. His athletic ability is off the charts, but he's having trouble winning with counter moves and seems to be out of his element a bit in coverage. It may be another year before we see what Collins can do in this defense.

Dee Milliner, Cornerback, New York Jets: Milliner is another player that's filled this space before, but it's worth mentioning how badly he struggled against the Bengals in Week 8. Andy Dalton targeted Milliner fives time, completing four passes for 108 yards and a touchdown. It's been a disaster of a rookie season for Milliner, and it continued last week.

Offense: Giovani Bernard, Running Back, Cincinnati Bengals

The Offensive Rookie of the Year race is going to come down to the wire. Giovani Bernard has been outstanding when given the ball, but his usage has been somewhat inconsistent. Meanwhile in Green Bay, Eddie Lacy has become the workhorse running back since he got healthy. Both players will end up making a strong case for the award at the end of the year and appear to be the clear front runners at the halfway point of the season.

Players that play in Sheldon Richardson's role aren't often filling up the stat sheet, but that shouldn't discount what he's done for the Jets defense. He's been a disruptive force in nearly every game he's played. While Sunday's game against the Bengals wasn't his best work, his body of work as a rookie has been remarkable. Bills linebacker Kiko Alonso is right on Richardson's heels as the season enters the second half.

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