Johnny Manziel has been tested by a great defense already this season.
Back on Sept. 8 the Texas A&M freshman quarterback faced Florida. The results weren't bad, but he made very few of his trademark big plays. His longest pass was 28 yards. Manziel has completed a longer pass in every other game this year. His longest run was 16 yards. He has had a run of at least 38 yards in every other game. He averaged 3.5 yards per run against the Gators -- 6.5 is his second-lowest average in a game.
That game seems so long ago, however. Manziel has emerged from a promising freshman making his college debut against the Gators to a legitimate Heisman Trophy candidate.
[Related: Texas A&M's next big SEC test]
Last week against Louisiana Tech, Manziel passed for 395 yards and ran for 181 more. He had six touchdowns, three passing and three rushing. Manziel goes from facing Louisiana Tech to preparing for Louisiana State this week. When it comes to defensive football, those two schools come from different worlds.
While Manziel has used his breakaway speed to beat most of the defenses he has faced, LSU has elite speed all across its defense. Tigers coach Les Miles said during the SEC conference call this week that he doesn't plan to use a spy on Manziel, and really, he probably doesn't need to.
"He's fast, but you'd be surprised how fast our d-linemen are," LSU middle linebacker Kevin Minter said, according to the Gannett News Service in Louisiana.
Still, LSU's defensive players all seemed quite surprised and impressed with Manziel's ability, particularly his speed, when they watched film this week.
"Oh, he left everybody," Minter said, according to Gannett News Service. "We watched that [Louisiana Tech] game a lot. He took off, just left them in the dust. When you have a mobile quarterback like that and everybody's back in coverage, you just never know. That boy can just take off."
While Manziel has been tested by Florida already, this is a great midseason test for the freshman, to see how far he has come and if he can put up Heisman-type numbers against one of the best defenses in college football. There should be plenty of excitement when the game kicks off in College Station at 12 p.m. ET, and that will start a pretty good day of football.
Here's the rest of what to watch in Week 8:
• Texas A&M-LSU will lead right into another fun SEC matchup, when No. 9 South Carolina goes to The Swamp to face No. 3 Florida (3:30 p.m. ET). This would have been perhaps the 
biggest game of the college football season to date had the Gamecocks beat LSU last week, but that's life in the SEC.
The Gators get a banged up South Carolina team, as running back Marcus Lattimore is unlikely to play because of a hip injury. The Gamecocks need this win to keep their hopes of making the SEC championship game alive, while the Gators can improve to 6-0 in conference play. Florida quarterback Jeff Driskel is coming off rushing for 177 yards, although it'll be a lot tougher to do that against the Gamecocks than it was against Vanderbilt.
Oh, and Florida legend Steve Spurrier returns to Gainesville. He is 3-4 coaching against the Gators.
• Kansas State and West Virginia face off (7 p.m. ET) in the third game of the week between ranked teams. Kansas State has climbed to No. 4, and the Mountaineers slipped to No. 17 after being handled by Texas Tech last week. But really, this game is all about the quarterbacks. Geno Smith's Heisman train is losing some steam after he completed 29-of-55 passes for 275 yards and a touchdown in that loss to Texas Tech. Collin Klein could benefit if he can outplay Smith on Saturday and keep the Wildcats undefeated.
Klein is coming off a 25-carry game, as the Wildcats continue to lean on him more and more. It's not a bad strategy. Klein has a chance to have a big game against a bad West Virginia defense, which could dramatically change the Heisman race.
• It seems we're getting bored with Alabama. The Crimson Tide are rolling through this season, again, and there isn't much buzz about them. Their closest game has been 19 points. They haven't given up more than 14 points in any game. Alabama is averaging 40.5 points per game. The Crimson Tide are great once again. Ho hum.
Tennessee's chances of challenging No. 1 Alabama (7 p.m. ET) looked better a month ago. The Volunteers have lost three of four games, the defense is struggling badly and Derek Dooley is under fire. We're all just waiting for Alabama at LSU on Nov. 3 at this point.
• Miami (Fla.) vs. Florida State (8 p.m. ET) could get a little ugly. The Seminoles look like they're playing angry after losing to NC State two weeks ago. Last week, Florida State took out some frustration in a 51-7 win against Boston College. The Seminoles now face a traditional in-state rival that will be far from full strength.
Quarterback Stephen Morris is dealing with a sprained left ankle. While he did practice some on Thursday, Morris is listed as doubtful according to CaneSport.com and backup Ryan Williams reportedly took all the reps -- although the media wasn't allowed to see that part of practice. Even if Morris surprises everyone and plays, he will probably be a step slow against a very tough defense.
• Virginia Tech and Clemson should have been one of the top matchups of the day (12 p.m. ET), but it has lost a lot of intrigue with the Hokies stumbling along at 4-3. Virginia Tech might have revenge on its mind after losing 23-3 at home during the regular season last year and then 38-10 in the ACC championship game a couple months later, but the Hokies will have to play a lot better than they've shown this season to beat Clemson. Is Virginia Tech the team that fell behind 20-0 at Duke last week, or the team that scored 41 straight points to rally for the win?
Clemson is 5-1, but its lone loss came to Atlantic Division rival Florida State, so the Tigers probably can't afford another loss if it wants to play for another conference championship.
[Related: Mike Riley's wild coaching ride has Oregon State cruising]
• BYU and Notre Dame (3:30 p.m. ET) has all the marks of a low-scoring, physical game. The Irish are allowing 287 yards per game, the 11th best mark in the country, but that's still well behind 
the Cougars' fifth-ranked defense that allows 260.9 yards per game. BYU's 42-24 loss last week to Oregon State was an unusually poor performance by its defense.
Neither offense is particularly explosive, and Notre Dame is still figuring out who will start at quarterback. Everett Golson is coming off a concussion, and while Tommy Rees has played a lot and bailed Notre Dame out a few times this season, coach Brian Kelly is saying that three quarterbacks are being considered for the start:
"Game-time decision," Kelly said, according to IrishIllustrated.com. Andrew (Hendrix) had a good week. They're all at that level where I can consider them. But I want to see Everett for 48 hours. I want to go all the way up there. I don't think there's a cookie cutter approach to concussions. You want to see how they handle exertion. You want to see how they handle all the things leading up in film study and watching and then get back on the field. I want to take the 48 hours that I have before I make that decision."
• The Big East has been surprisingly strong with three ranked teams, and two games in the next two weeks will provide some clarity to the race. Next Friday, Cincinnati and Louisville face off, but before then, Rutgers and Temple square off (12 p.m. ET) to determine who will be in first place at week's end.
Rutgers is 3-0 in the conference and Temple is 2-0, and this game is at Temple. The Owls are coming off a win against South Florida and a road win at UConn, so they should have some confidence. Temple's biggest challenge is bottling up Rutgers running back Jawan Jamison, who rushed for just 64 yards last week against Syracuse, the first time he hasn't reached 100 yards rushing in a game this season.
• Cincinnati and Toledo play one of the most intriguing games of the day (7 p.m. ET). Toledo is 6-1, with just an overtime loss at Arizona keeping the Rockets from being undefeated. The Bearcats are undefeated at 5-0, ranked 21st, but this will be a tough challenge.
Cincinnati's defense has been solid, allowing just 14.4 points per game, but it better be ready for Toledo. The Rockets are averaging 44.3 points over their last four games. Quarterback Terrance Owens passed Austin Dantin, Toledo's starter the past two years, on the depth chart and has been exceptional. Owens is a good dual threat who the Bearcats could have some problems with.
• The Cal-Stanford rivalry gets renewed this Saturday (3 p.m. ET), and the game also marks the 30th anniversary of Cal's famous multiple-lateral touchdown on the final play to beat Stanford. SI.com ran a great oral history of "The Play" this week, and hey, it's never a bad thing to relive one of the greatest plays in the sport's history:
• Northwestern has been fantastic this season other than one quarter at Penn State, when it blew a big lead and dropped its only game of the season. The 6-1 Wildcats beat Minnesota last week, and can reestablish themselves as a legitimate contender in the Big Ten's Legends Division by beating Nebraska (3:30 p.m. ET). The Cornhuskers are a respectable 4-2 but have been surprisingly vulnerable on defense. They gave up 63 points to Ohio State on Oct. 7, the most points allowed by a Nebraska team since 2007. Nebraska had a bye week to figure out its issues on defense, and also come up with a plan to contain Northwestern's do-everything quarterback Kain Colter.
• Mississippi State is 6-0, coming off a very nice win against Tennessee and has climbed to No. 15 in the country. Next week, the Bulldogs play an enormous game at No. 1 Alabama. 
That's what makes this week tricky.
[Related: MSU's Johnthan Banks' appetite for success grew from his work with horses]
The Bulldogs host Middle Tennessee (7 p.m. ET), which is sandwiched between two emotionally charged conference games. And the Blue Raiders are pretty good. Senior running back Benny Cunningham is done for the season with a knee injury, and he carried Middle Tennessee to an upset against Georgia Tech with 217 yards and five touchdowns. That's a big blow, but Middle Tennessee averages 33 points per game and it wasn't just because of Cunningham. The Blue Raiders defense might have a problem with Mississippi State's improved passing game, but this is a game the Bulldogs better take seriously.
• Duke gets its second crack at bowl eligibility after blowing a huge lead to Virginia Tech last week, and what better way to get that sixth win than to do it at home against rival North Carolina (7 p.m. ET)? Both teams have identical records at 5-2 with a 2-1 conference mark.
Or is Duke bowl eligible already? As DukeHoopBlog.com pointed out, the NCAA is allowing 5-7 teams to be selected if there are not enough bowl eligible teams or a bowl can't be filled with its conference affiliations, if the five-win team has a top five score in Academic Progress Rate, which Duke does. The six-step tiebreaker procedure is outlined by the blog, and the 5-7/APR exception is No. 6, so the Blue Devils might want to lock up bowl eligibility with a sixth win, just to make sure.
• There aren't many trash-talking moments that have turned out as poorly as Mike Hart's "little brother" comment.
After beating Michigan State in 2007, then-Michigan tailback Hart gave the Spartans all the motivation they would need for a few years, calling the Spartans the Wolverines' "little brother."
After hearing about the comments, Michigan State coach Mark Dantonio said the Wolverines "need to check themselves sometimes."
"Let's just remember, pride comes before the fall," Dantonio said.
Michigan hasn't beaten the Spartans since. The Wolverines have a chance to break the streak this week (3:30 p.m. ET) against a Spartans team that has been a pretty big disappointment this season. But as the past four meetings have shown, the Spartans always have a little extra motivation for this rivalry game.
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