A talented running back whose college career was marred by nasty knee injuries in back-to-back seasons? The 49ers now have three players who fit that description.
Frank Gore's and Marcus Lattimore's stories are well known. You probably haven't heard as much about Boise State running back D.J. Harper, one of the undrafted free agents the 49ers signed this week.
Harper tore his ACL in successive seasons. Unlike Gore and Lattimore, who tore ligaments in different knees, both of Harper's injuries occurred to his left knee and both occurred in the third game of the season in 2009 and 2010. He was granted a rare sixth season of eligibility at Boise State, and last season ran for 1,137 yards and scored 15 touchdowns.
GM Trent Baalke wants a stable of running backs with varied skills, and Harper (5-9, 209) fits the mold of the outside runner. He's a good receiver out of the backfield, and he ran the 40-yard dash in 4.48 and 4.49 seconds at Boise State's pro day in March.
Of course, ACL injuries are a theme this year for the 49ers. Three veteran players - Darius Fleming, Mario Manningham and Kyle Williams - are recovering from the injury. So are Lattimore and fellow draft pick Tank Carradine. Lattimore also tore his PCL and LCL and dislocated his kneecap.
One more injured player - undrafted free agent Luke Marquardt. The huge offensive tackle - he stands 6-9 - suffered a hairline fracture in his foot before last season and did not play his senior year at Azusa Pacific in Southern California. Marquardt has some of the elements that make fellow undrafted free agent Lawrence Okoye intriguing. Marquardt obviously has impressive size like Okoye, and he doesn't have much of a football background, either. He didn't play in high school and essentially had to learn how to play tackle as a freshman at Azusa.
An addendum to yesterday's item on arm length ... Long arms only are effective when they're coupled with power. Many times, a player with long arms doesn't register as many repetitions of 225 pounds as a player with shorter arms simply because he has to lift the weight a greater distance. That wasn't the case with this draft class, many of whom had high marks in the bench-press category. Alabama defensive lineman Quinton Dial appears to have gone through the run-up to the draft without having to perform the bench-press test.
DL Tank Carradine -- 32 reps
OT Luke Marquardt - 31 reps
TE Vance McDonald - 31
DL Lawrence Okoye - 30 reps
OLB Corey Lemonier - 27
-- Matt Barrows