EUGENE — One day after learning they lost their most experienced defender for the Oregon football season, the Ducks found out Monday they'll be without their most experienced offensive player for the rest of the year, too.

EUGENE — One day after learning they lost their most experienced defender for the Oregon football season, the Ducks found out Monday they'll be without their most experienced offensive player for the rest of the year, too.

Senior guard Carson York said he'll undergo season-ending surgery to repair a broken knee cap suffered Saturday against Fresno State. York played in reserve each of the Ducks' two games this season after coming back from a patellar tendon tear suffered in the Rose Bowl, which he said was unrelated to the latest setback.

"(It's) sort of like, they repaired the cable and instead of the cable breaking again, the wall broke," said York, always one of Oregon's most quotable players.

His announcement came a day after senior safety John Boyett confirmed he needs season-ending surgery on both knees. The injuries almost certainly end the collegiate careers of each, Boyett's after 40 career appearances with 36 starts, and York's after 42 appearances with 36 starts.

"He's a captain," UO center Hroniss Grasu said of York. "It's tough seeing a guy work so hard this whole offseason to get back to where he got back to. Seeing him set back like that, makes you feel really bad for him."

York was the last remaining player on the roster who started on offense or defense in Chip Kelly's head coaching debut, at Boise State in 2009. Boyett entered that game as an injury replacement for T.J. Ward; current Ducks Kenjon Barner, Michael Clay, Jackson Rice and Rob Beard also played that night.

"From a leadership standpoint, you can't replace him from that standpoint," UO offensive line coach Steve Greatwood said. "No matter what happens with him with this setback now, I'm still counting on him being a leader, and he will be."

York was hurt in the second half Saturday, then left the field in the middle of a drive and appeared to be in agonizing pain as team medical staff examined him on the bench. He watched the rest of the game from the sideline with ice wrapped around the knee.

"Initially, (I was) pretty upset, but if you think about it I'm a pretty lucky individual," York said. "I'm not going to sit here and give the Lou Gehrig 'luckiest guy alive' speech, but the experience I got to have over last four or five years, however long I've been here, is a whole lot more than I ever thought I'd get.

"What this team has become over the last three or four years, as far as the culture around here, is pretty amazing. I'm blessed, happy, and I will be around every day for the rest of the year. I have just as much invested in the success of this team as I did before."

York's injury was seemingly the most severe, and the one with the worst long-term implications, but it was just one of several that hampered Oregon's offensive line against Fresno State on Saturday.

Senior Kyle Long didn't play because of an ankle problem, sophomore tackle Jake Fisher was out by halftime with a lower leg problem, and starting guard Ryan Clanton was standing on the sideline without a helmet in the second half, typically indicating a head injury.

Those injuries — and an all-out assault by the Fresno State defense — wreaked havoc on Oregon's offensive consistency for much of the second half. Senior Nick Cody, who started both games at right guard this season but shifted out to tackle Saturday after Fisher's injury, said the Bulldogs blitzed much more often in the second half than the Ducks anticipated based on their film study.

"They did a nice job defensively of basically giving a seven-, eight-man front and creating some confusion as to where they were coming from on the blitz," Greatwood said. "Sometimes we picked it up well, and other times we didn't, and that was very evident to anybody that was in the stands watching."

Oregon's offensive timing was also upset by an inconsistent night snapping the ball from Grasu. He said Monday he saw a technical flaw in his release while analyzing game film, which he fixed in practice to positive reviews from coaches and teammates.

"It's kind of like your golf swing — when it sort of goes, you've got to step back and find a way to fix it," Greatwood said. "We're working hard on it this week, and I don't anticipate it being an issue."

Because of the injuries to so many front-line players, Oregon's backup guards got extensive playing time Saturday, and figure to do so going forward given York's status and that Fisher was again in a walking boot Monday. Mana Greig, who came to Oregon as a walk-on, and Hamani Stevens, who returned to the team last fall after a church mission, were on either side of Grasu for much of the second half.

Stevens, perhaps the strongest player on Oregon's offensive line, has showed off some impressive footwork too at times this season. In the opener he deftly hurdled a prone defensive lineman to continue upfield as a blocker, and on one play Saturday he was some 20 yards upfield helping clear the way for a run by quarterback Marcus Mariota.

Greatwood said Stevens "can be fantastic" at times, which the Ducks are looking for on a more consistent basis.

"He's tough, and when he gets into games he's working his butt off to finish blocks," Cody said. "For him, it's a matter of confidence. I've seen him come off the ball and bury people, and the only time he doesn't try to do that is when he's not sure what he's doing. The best thing we can do is, especially when I'm at tackle, is comfort him any way we can by making those calls and making sure he's confident.

"Once he's confident and can project that, I think you're going to see that effort every single play."