One of the quickest ways for a successful season to go south is an injury to a key player or two. Stanford looks pretty healthy heading into their Aug. 31 opener against San Jose State, but there are a few guys coach David Shaw will want to keep his eye on.

FB Ryan Hewitt -- sprained ankle: Hewitt sprained his right ankle during Stanford’s scrimmage Sunday according to the San Jose Mercury News. Coach David Shaw, who’s not big on talking about injuries, only offered a short comment on the Hewitt injury, “Hopefully it’s not too bad.” Right now it’s too early say if Hewitt will be out any serious length of time, but if he is, that will be a blow to the Stanford offense. Hewitt is a versatile fullback who not only blocks and runs, but he’s also threat to catch the ball out of the backfield. Hewitt was third on the team in both receptions (34) and touchdown catches (5) last year.

LB Shayne Skov -- returning from knee injury: Skov hasn’t played in a game since tearing his ACL and MCL against Arizona in week 3 of last season. If the senior linebacker can return to his 2010 form -- when he led the team in tackles -- then the Cardinal linebackering corps could be one of the strongest units in the Pac-12. Stanford fans won’t get a chance to see if Skov is healthy until Sept. 8; the 6-3, 242-pound linebacker is suspended for the opener against San Jose State as punishment for a DUI he received in February.

OL Cole Underwood: Underwood might be Stanford’s biggest loss this season. Shaw announced on Aug. 14 that a knee injury that underwood suffered was “more serious than we had hoped.” Shaw followed that up by saying he expects Underwood to miss the 2012 season. The loss is a blow to Stanford’s offensive line depth. Underwood was expected to backup David Yankey at left guard; he was also capable of playing right guard and tackle.

Other injury concerns: Skov won’t be the Cardinal defensive player returning from an injury. CB Wayne Lyons is returning from a broken foot he suffered last season. “He’s still at that point where he’s not injured, but he’s not 100 percent,” Shaw said of Lyons.

Safety Ed Reynolds, who missed the 2011 season with a knee injury, will be expected to contribute this season. He could end up being Stanford’s starting free safety. Right now Reynolds is battling Devon Carrington for the starting spot. 

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