5 feet 11, 225 pounds
On the chart: Fits the mold of the power back but has the speed to break away, as he demonstrated almost daily during spring practice. Might be tough for him to crack the starting lineup, but he is forcing coaches' hand to play more.
Last year: An outstanding special teams player, he got only 15 carries but turned two of his three pass receptions into touchdowns.
Highlight reel: Caught touchdown passes against Washington State and Notre Dame, but his greatest contribution has been his inspired play on special teams.
6 feet, 200 pounds
On the chart: Started five games as a freshman, including the 2006 opener, and the first two games last season before a lingering abdominal injury slowed him and ultimately required surgery. Does everything well, including pass block.
Last year: Rushed for a team-high 68 yards against Idaho and had a 40-yard run against Nebraska, but his physical condition worsened against Washington State and he opted to redshirt.
Highlight reel: Former Sylmar High star became USC's first true freshman tailback to start an opener two years ago against Arkansas, a testament to the consistency and work ethic he has exhibited from day one.
6 feet 2, 235 pounds
Little Rock, Ark.
On the chart: Will have a hard time moving past the more experienced quartet of Joe McKnight, Stafon Johnson, Allen Bradford and C.J. Gable, but his powerful style could give the Trojans a dynamic short-yardage threat and possibly more.
Last year: Was impressive during training camp scrimmages but a foot injury suffered during one of them ultimately required surgery and forced him to redshirt.
Highlight reel: "He's a horse, dude. That guy trucks," former quarterback John David Booty said after Green averaged nearly eight yards a carry in a scrimmage last year. "You think he's going to be down and he just keeps going and going."
5 feet 11, 215 pounds
On the chart: The former Dorsey High star, perhaps the Trojans' most instinctive runner, could assume a starting role now that the foot injury that slowed him last year is healed.
Last year: Appeared on his way to a breakout season before he got hurt in the fourth game at Washington. He did not return to near full speed until the end of the season and rushed for 104 yards in the Rose Bowl.
Highlight reel: Had a 144-yard effort against Nebraska that was tempered some after the Cornhuskers' defense was exposed, but there was no debating his power, speed and balance. He also eclipsed 100 yards rushing against Washington and Illinois.
6 feet, 200 pounds
River Ridge, La.
On the chart: The Trojans want to expand McKnight's role to something similar to the way Reggie Bush was deployed in 2004 -- as a running back, receiver and punt return specialist. He could wind up with the most touches among tailbacks.
Last year: Mainly a backup, he averaged nearly six yards a carry. His 45-yard punt return and 59-yard run in the fourth quarter against Arizona set up a USC victory.
Highlight reel: A 206-yard all-purpose effort in the Rose Bowl victory over Illinois put McKnight on Heisman Trophy watch lists for 2008. His spectacular 65-yard run after a bobbled lateral was his season in a nutshell.
6 feet, 220 pounds
On the chart: Appears to have recaptured the burst of speed that had been absent since he suffered a broken leg in high school. He is likely to get some opportunities if he can eliminate mistakes that plagued him in the spring scrimmage.
Last year: The aftereffects of his broken left leg forced him to redshirt.
Highlight reel: Son of former UCLA star Wendell Tyler showed flashes of his speed and breakaway acceleration during spring practice and has continued to impress in training camp.