For many teams, one-third of the college football season is in the books.  Teams are starting into get into the meat of their schedules, and as a result, fans and NFL scouts are seeing some important and exciting matchups that go a long way toward determining both a team’s success and a prospect’s NFL Draft value.  Here is a look at some of the risers and sliders through the first four weeks of the season.

Many talent evaluators touted Arkansas running back Knile Davis as a potential first round draft pick prior to the season.  But the Razorbacks runner managed just 10 carries for 17 yards against Rutgers on Saturday, giving him a grand total of 208 rushing yards (52 yards per game) through four games.  Davis is averaging just 3.3 yards per carry – down from 6.5 during the 2010 season – and has scored only two touchdowns so far.  He looks like he is struggling to regain the burst and speed he had during that 2010 season in which he helped lead Arkansas to a BCS Bowl.  It appears that Davis is not yet 100% healthy; and that, coupled with the team’s overall lackluster play, is causing his draft stock to take a weekly hit.  The Rutgers game was a low point, but Davis has struggled against all levels of competition.  Even against FCS Jacksonville State, he only mustered 3.9 yards per carry on 18 attempts.  There is no question that Davis is a gifted athlete, but he is going to have to start producing on the field sooner or later.

Wisconsin running back Montee Ball’s nightmare senior season continued in Saturday’s win over UTEP.  Not only did he fumble for the first time in his collegiate career, but he was also forced to leave the game due to a head injury.  Couple that with the concussion he suffered in an offseason assault, and it could become a red flag when he gets medical checks from NFL teams.  Ball is averaging just 3.9 yards per carry, down from 6.3 last year.  His receiving ability was a major part of his appeal last season, but he has only seven catches in four games thus far.  Ball (along with the entire Badger offense) appears to be missing departed stalwarts Russell Wilson, Kevin Zeitler, and Peter Konz.  Defenses are keying in on him and daring Wisconsin’s sub-standard quarterbacks to beat them.  Redshirt freshman Melvin Gordon had 112 yards on 8 carries in relief on Saturday, so now Ball is in danger of losing some playing time regardless of when he returns from the injury.  His decision to return to Madison for his senior season has been nothing short of a disaster to this point in the year.

Florida State’s senior running back Chris Thompson had fallen off the radar (well, my radar anyway) after breaking his back and missing most of the 2011 season.  Through the first two games he carried the ball only nine times for 57 yards.  Then, in a win over Wake Forest, Thompson added nine more carries and exploded for 197 yards.  In addition, he ran for two touchdowns, including an 80 yarder.  Saturday, against Clemson, Thompson logged 15 carries, amassed 103 rushing yards, and ran for two more touchdowns.  In addition, he hauled in a career best eight passes for 79 yards.  Thompson stands just 5’8 and 187 pounds, but he has speed estimated in the 4.3-4.4 second range in the 40.  On Saturday he showed quick feet, terrific open field moves and a surprising ability to finish off runs.  Thompson is not going to be an every down running back in the NFL, but he is forcing scouts to take notice.  Versatile running backs with speed and receiving ability are intriguing weapons to creative offensive coordinators.  While Davis and Ball are taking a hit, Thompson is creating a draft stock that may have barely existed earlier this season.

Thompson’s more famous teammate, quarterback E.J. Manuel, has looked like the player many people thought Logan Thomas would be before this season began.  Manuel pulled off a tremendous performance against Clemson Saturday night, going 27 for 35 (77.1%) for 380 yards, two touchdowns, and zero interceptions.  To top it off, he added 12 carries for 102 yards on the ground – the first 100 yard performance of his career.  Manuel was stepping into his throws showing good form on his drop backs.  He stayed poised in a close game where both teams were lighting up the scoreboard.  He’s completed 73.4% of his passes, with 8 TDs and only one INT through four games.  Manuel hadn’t faced any real competition through the first three games of the season, but when he finally faced a ranked opponent in a nationally televised game, he came up with his best game as a collegian to date.

The aforementioned Logan Thomas was drawing comparisons to Cam Newton and Ben Roethlisberger over the summer, but he isn’t living up to the hype early on.  In his last two games (a loss to Pitt and a win over Bowling Green) Thomas is just 25 for 56 passing (43.9%), with three touchdowns and four interceptions.  He has completed just 51.7% of his passes so far this year; and despite some late game heroics against Georgia Tech in the Hokies’ opener, his season has been a disappointment.  Thomas has excellent velocity on his throws and can make some passes that will wow onlookers, but he is just too erratic with his ball placement.  It’s still early, but at this point he may want to strongly consider returning to Blacksburg for his senior season in 2013.

USC quarterback Matt Barkley has thrown just two touchdown passes and four interceptions in his last two games.  He followed an uncharacteristically shaky loss to Stanford two weeks ago with a ho-hum showing against Cal on Saturday.  Barkley is averaging just 6.1 yards per attempt in his past three games since beating up on Hawaii in the Trojans’ opener.  Despite reports over the summer that he had improved, he simply doesn’t possess the type arm strength that scouts look for in a high first round draft pick.  Once considered by many a favorite to win the Heisman and be drafted first overall, Barkley has been left in the dust so far by West Virginia quarterback Geno Smith.  Barkley lacks the physical tools and size of the top QB prospects of the past few years, so he needs to be accurate and poised to be at his best.  But in recent weeks, not only does he not look like a number one pick, he doesn’t even look like a potential first round draft choice.

Georgia linebacker Jarvis Jones has 6.5 tackles for loss, 3.5 sacks, two forced fumbles, two pass break ups, and an interception in just three games this season.  Despite missing a game against Florida Atlantic with a groin injury, Jones looks like a legitimate top ten prospect; and against Missouri he looked like perhaps the best defensive player in all of college football.  Still, no matter how well Jones plays this season he’s unlikely to end up being the number one overall pick.  The last time a linebacker was picked number one was all the way back in 1988 when Aundray Bruce went to Atlanta with the top pick.  In fact, the last time any defensive player went first overall was in 2006 when Mario Williams went to the Texans.  Still, Jones is one of the best players in college football and is proving that his 2011 season was no fluke.

Jones’ Georgia teammate Marlon Brown has 16 catches for 264 yards (16.5 yards per catch) and three touchdowns – all career highs for a season – through just three games this year.  In Saturday’s win over Vanderbilt, the senior wide receiver hauled in five passes for 114 yards and a touchdown.  Brown now has two 100-yard games this year after having only one over the course of his first three seasons in Athens.  Brown isn’t a burner but at 6’5 and over 220 pounds he provides a huge target, and viable red zone threat, for quarterback Aaron Murray.  It appears as if the former four-star recruit appears to be finally reaching his potential.

Southern Methodist defensive end Margus Hunt was a trendy first round prospect over the summer, seemingly based off of one heroic bowl game performance against Pitt last year.  Hunt is also known as an expert kick blocker, with 16 blocks in his career; but this is not a skill that translates well to the NFL game where kickers and special teamers are far more skilled.  So far this year Hunt has two blocked kicks; but just five tackles, one tackle for loss and one sack.  Not only is he not producing, he doesn’t always appear to be giving optimum effort.  Hunt will also turn 26 prior to the 2013 NFL season.  Without better production in the defense his stock will continue to be based almost solely on the premise that he is a physical freak (6’8 280 pounds and 4.6 speed in the 40), thus making him a huge risk to any team considering him in the first couple of rounds next April.