SANTA CLARA The advantage of having an already-loaded roster on draft day is a team can gamble.
The 49ers did that in the fourth round Saturday, selecting one of the most talented running backs in the nation but one who suffered perhaps the most gruesome injury of 2012.
South Carolina's Marcus Lattimore already had scored a touchdown and gained 65 yards by the second quarter on Oct. 27 when he was submarined by a Tennessee defender and immediately clutched his right knee. The hit left him with three torn ligaments, a dislocated kneecap and six months of intense rehabilitation.
The injury was doubly painful considering he had suffered a torn ACL in the other knee the previous season.
"Right after it happened, I doubted myself," Lattimore said Saturday when asked if he ever gave up on making it to the NFL. "I did do that, and I lost hope."
Any 49ers fan knows that Frank Gore also suffered two devastating knee injuries at the University of Miami, and Chris Culliver saw the similarities, too. The former South Carolina cornerback, whose locker is close to Gore's, put Lattimore in touch with Gore shortly after the injury.
Lattimore said Gore, as well as Broncos running back Willis McGahee, who tore three knee ligaments in the 2003 Fiesta Bowl, were inspirations when he was at a low point.
"He knew he could come back from what he had, and he worked hard, and he was determined to come back," Lattimore said of Gore. "He came into the league, and he's been doing his thing for a while. He just kept that positive mindset."
Gore also is the reason there's no rush to get Lattimore onto the field this season. Gore rushed for 1,214 yards last season, the second-highest total of his career, and is signed through the 2014 season. Still, he turns 30 next month, and the 49ers must try to find his replacement.
General manager Trent Baalke said he prefers a three-headed approach at running back three players with varying talents who can be rotated in and keep defenses off balance. Lattimore would seem to be a good eventual replacement for Gore's straight-ahead style.
Lattimore, who weighs 233 pounds, averaged 4.8 yards a carry in three seasons at South Carolina and scored 38 rushing touchdowns despite his injuries.
"Unique player, unique person," 49ers coach Jim Harbaugh said. "Can't say enough about his mental toughness. We're betting that his physical athleticism, his approach, his attitude, his work ethic that he'll be able to overcome the setbacks he had last fall."
Lattimore said he has been sprinting for the last two weeks, but Harbaugh said the 49ers would like to slow down the running back's rehabilitation and make sure he's strong for the future. San Francisco could stash him on the non-football injury list in 2013.
"If he doesn't play this year, he doesn't play this year," Harbaugh said.
The team also looked ahead at wide receiver, drafting Louisiana Tech's Quinton Patton three spots before Lattimore.
The 49ers already had plenty of wide receivers, but three prominent ones Anquan Boldin, Mario Manningham and Kyle Williams are signed only through the upcoming season. Manningham and Williams are coming off ACL injuries.
Patton, meanwhile, was prolific in college, finishing with more than 1,200 yards in the last two seasons and having some of his best games against highly ranked opponents. For example, he finished with 233 receiving yards and four touchdowns against then-No. 22 Texas A&M last year.
San Francisco general manager Trent Baalke was in the stands that night.
"The lights weren't too big for him; they weren't too bright," he said, noting that Patton also fared well in the Senior Bowl.
The 49ers also drafted a quarterback, South Florida's B.J. Daniels, in the seventh round. He is capable of running the read-option plays Colin Kaepernick handled so well last season.
After the draft, San Francisco added former British discus thrower Lawrence Okoye, who at 6-foot-6 and 305 pounds will be given a shot at defensive end.
49ERS REPORT CARD
Replace safety Dashon Goldson and tight end Delanie Walker and create better depth at aging areas such as defensive line.
The 49ers used two of their first three picks on safety Eric Reid and tight end Vance McDonald, who will be expected to contribute during their rookie seasons. Mostly, however, they looked ahead. Two of the picks, "Tank" Carradine and Marcus Lattimore, are coming off major injuries. It may be that neither has a big role in 2013. That's OK. There is no crucial need for either to play right away, but there could prominent openings for both talented players in coming years. At that time, the gamble on injured players could pay off handsomely for San Francisco. Quarterback B.J. Daniels gives the 49ers, at the very least, an excellent practice player, while undrafted Olympic discus thrower Lawrence Okoye is an enticing project.
THE NEWEST 49ERS
Selected: 128th (fourth round)
College: Louisiana Tech
Position: Wide receiver
Height, weight: 6-0, 202
Comment: Patton is a prolific and confident receiver who had more than 1,200 receiving yards the past two seasons. Some of his best games came against top competition, including a 233-yard receiving effort vs. Texas A&M last year.
Selected: 131st (fourth round)
College: South Carolina
Position: Running back
Height, weight: 5-11, 233
Comment: He was perhaps the best running back in the nation before a devastating right knee injury ended his season. He has a story line similar to Frank Gore's and could be Gore's heir.
Selected: 157th (fifth round)
Position: Defensive lineman
Height, weight: 6-5, 318
Comment: The 49ers hadn't used a draft pick on the defensive line since 2009 but took two in this draft. Dial has prototypical size and can play all three positions on the line, including nose tackle.
Selected: 180th (sixth round)
College: Florida State
Position: Inside linebacker
Height, weight: 6-1, 236
Comment: Moody has potential at inside linebacker after mostly playing safety at Florida State. The 49ers drafted him, however, because he's a special-teams ace.
Selected: 237th (seventh round)
College: South Florida
Height, weight: 5-11, 217
Comment: He'll get to compete at quarterback but could land a roster spot because of his versatility. He'll also be looked at as a reserve wideout and running back, and may return punts this offseason.
Selected: 246th (seventh round)
College: Iowa State
Position: Offensive tackle
Height, weight: 6-7, 306
Comment: Like 49ers left tackle Joe Staley, Bykowski began his college career as a tight end. He has played both right and left tackle, and will compete with Kenny Wiggins (Elk Grove High School) to be the 49ers' swing tackle in 2013.
Selected: 252nd (seventh round)
Height, weight: 6-2, 192
Comment: Tall cornerbacks are all the rage in the NFL, and Cooper has both height and excellent athleticism. However, he was not a full-time starter in his final season at Rutgers.