Two 49ers defensive standouts were among those placed on the physically-unable-to-perform list Tuesday upon reporting to training camp in Santa Clara.
Linebacker Dre Greenlaw and safety Talanoa Hufanga, coming off significant injuries sustained last season, will continue physical therapy until they receive medical clearance to return to action.
The 49ers placed rookie wide receiver Ricky Pearsall (hamstring) on the non-football injury list last week. He sustained the injury while working out, general manager John Lynch said. The team expects Pearsall to be cleared for practice by next week.
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Defensive end Drake Jackson also was placed on PUP as he continues to rehab from knee surgery last season.
Players who are placed on the PUP list at the beginning of camp can be removed at any time. If a player opens the regular season on PUP, he must sit out at least the first four games.
Greenlaw suffered a torn left Achilles in the first half of the Super Bowl as he sprung forward to enter the playing field for a defensive series. He underwent surgery four days later.
Greenlaw is not expected to be ready for the 49ers’ season opener on Monday, Sept. 9, against the New York Jets.
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“When I feel like I can go out there and I really contribute and bring everything I got, I'm just going to do that every game,” Greenlaw told NBC Sports Bay Area in May. “I don't know if it's going to be two, three, five, six, eight or 10 (games). But when I do get the opportunity, I'm just going to play like it's the Super Bowl every game.”
Hufanga, who was coming off a season in which he earned AP All-Pro honors, sustained a torn anterior cruciate ligament in his right knee in the 49ers’ victory over Tampa Bay on Nov. 19 at Levi’s Stadium.
Hufanga anticipated opening training camp on the PUP list when he last met with reporters in June. He stated his goal was to do everything necessary to be ready for Week 1 of the regular season.
"Obviously, it's a give or take at any time, but the goal is to be ready by Week 1," Hufanga said. "The goal is to be in training camp, not the very beginning, but to ramp me up correctly so it's not just a throw you out to the wolves and 'good luck.'
"But trying to be smart with it, we've had plenty of discussions with the training staff and putting me in the best possible situation to succeed for myself and then try to help the team as well."