PITTSFORD, N.Y. (AP) -- Knee injuries keep getting in the way of Buffalo's quarterback competition. The latest one may even have decided it temporarily.
Bills coach Doug Marrone said Sunday that rookie E.J. Manuel had a "minor procedure" on his left knee Sunday morning. Marrone declined to elaborate on the exact nature of the procedure but said that Manuel will miss the remainder of the preseason. After two weeks, he will be considered day to day.
"I understand that he's not going to be here for the preseason but any time after that right now my expectation is he'll be day to day," Marrone said.
Marrone added that there's a "good chance" Manuel will be ready for the start of the season.
Kevin Kolb, who is competing with Manuel for the starting job and had been outplayed in games so far, missed more than a week after twisting his left knee after he tripped on a wet mat while going between Buffalo's practice fields.
Manuel was hurt in Buffalo's preseason game against the Minnesota Vikings on Friday. He left the game at the end of the third quarter and did not show any signs of injury afterward. But there was swelling in his left knee Saturday morning, and the Bills announced the injury in a statement later that afternoon.
"After the game was over, (he) felt a little bump, we checked, stability was good and really that night that's all that we were going on," Marrone said. "The next day I think is the most important thing to focus on. There was a little bit of swelling, obviously then you get a concern. Our staff obviously checked him out with an MRI, saw something, went through a minor procedure."
Manuel told Marrone that he believed the injury occurred on the QB's sixth play of the game when Manuel scrambled to his right for a five-yard gain. That play was called back on a holding penalty. Manuel finished that series, leading the Bills on a 14-play, 80-yard touchdown drive and would play two more series before leaving the game as planned.
Kolb noticed something was wrong with Manuel after that scramble.
"You can tell when you're around a guy a lot and the way he runs and the way he acts and the way he grimaces, it just looked like something was a little wrong," Kolb said. "And when he came to the sideline, he really wasn't talking to anybody that much, so I could tell something was on his mind and I just left him alone."
The injury comes at a difficult time for both the Bills and Manuel, and it appears to have changed the entire complexion of Buffalo's preseason. Prior to the injury, Manuel looked to have taken the edge in the quarterback competition over the veteran Kolb. Manuel completed 26 of 33 passes for 199 yards and two touchdowns and ran four times for 29 yards in two preseason games. Manuel has displayed a good amount of composure and poise throughout training camp and has been a more consistent passer than Kolb.
The Bills have high hopes for Manuel, who is regarded as the future of the franchise. Buffalo chose the strong-armed passer 16th overall out of Florida State. At 6-foot-4, 237 pounds, Manuel is a dual-threat quarterback who is dangerous with both his feet and his arm.
"It's a tough break for EJ, but he's a hard working kid," center Eric Wood said. "He's going to get after it and do what he needs to do to come back and play. ... The sooner we can have him back the better."
Kolb who is 13-for-21 with an interception and no touchdown passes, will start Buffalo's next preseason game on Saturday against Washington.
The Bills signed the six-year veteran this offseason after he was released by Arizona. Kolb, a former second-round pick of the Philadelphia Eagles, has thrown for 5,206 yards, 28 touchdowns and 25 interceptions in his career.
"I've been in this situation before," Kolb said. "There's been times I've had to come in when guys got injured after games and something like this popped up ... so it's nothing new for me."
NOTES: The Bills released four players on Sunday: offensive lineman Tony Hills, defensive back Mark LeGree, wide receiver Terrell Sinkfield and defensive back Don Unamba. They also placed wide receiver Kevin Elliott on injured reserve. Elliott suffered a torn knee ligament Friday against Minnesota.
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