How does the Bills' season get worse? A player retired at halftime

As if Bills coach Sean McDermott didn't have enough to worry about in trailing the Chargers 28-6 at halftime on Sunday, he had to contend with veteran cornerback Vontae Davis quitting on the team.

"Pulled himself out of the game. He communicated to us that he was done," McDermott revealed after a 31-20 loss. McDermott provided no other details except to bluntly say, "No," when asked if Davis was injured.

Teammates peeved

The Bills two veteran defensive leaders were far more upset with Davis essentially going AWOL.

"I don't have nothing to say about Vontae. I'll give him a little bit more respect than he showed us today as far as quitting," defensive end Lorenzo Alexander said.

"He didn't say nothing to nobody," Alexander added. "You know as much as I know. I found out going into the second half of the game. They said, he's not coming out. He retired."

Tackle Kyle Williams said he's never encountered a player ever quitting on a team during a game.

"I think the only thing to say is he's where he needs to be right now," Williams said. Asked where that was, he responded: "That's not here, point blank and simple."

Davis issued a lengthy statement posted on the NFL's Twitter account, announcing he is retiring after 10 seasons.

"This isn't how I pictured retiring from the NFL," he wrote. "But today on the field, reality hit me fast and hard. I shouldn't be out there anymore."

Davis said he meant no disrespect to Bills players and coaches.

"I hold myself to a standard. Mentally, I always expect myself to play at a high level," he wrote. "But physically, I know today that isn't possible and I had an honest moment with myself. While I was on the field, I just didn't feel right, and I told the coaches, 'I'm not feeling like myself."'

Davis was credited with one tackle.

McCoy dealing with multiple rib fractures

Buffalo Bills running back LeSean McCoy fractured multiple ribs in Sunday's loss to the Los Angeles Chargers, NFL Network reported Monday morning.

McCoy left the game after rushing nine times for 39 yards. The Bills are 0-2 following the 30-21 loss to the Chargers.

NFL Network reported McCoy will attempt to play through the injury when Buffalo plays the Minnesota Vikings this week.

Running back Taiwan Jones left the game against the Chargers in the third quarter after he took a brutal hit to his head in the end zone.

Defence wilts in 1st half

The Bills provided Davis a chance to re-start his career by signing him to a one-year contract in March after a dispute with former Colts coach Chuck Pagano led to Indianapolis cutting him in November.

Davis made his Bills' debut against the Chargers after being inactive against Baltimore last week.

Davis' abrupt departure overshadowed a defence that wilted in the first half in allowing the Chargers to score touchdowns on four consecutive drives, and a week after a 47-3 meltdown in a season-opening loss at Baltimore.

McDermott also revealed he took over the defensive playing-calling from co-ordinator Leslie Frazier in the second half.

QB Allen's debut overshadowed

The numerous developments overshadowed rookie first-round draft pick Josh Allen's debut at quarterback.

Allen struggled through much of the first half in going 8 of 14 for 126 yards, and leading the Bills to score two field goals.

The 22-year-old was better in the second half, which he began by overseeing a seven-play, 75-yard drive capped by Chris Ivory's one-yard plunge .

Allen finished 18 of 33 for 245 yards passing with a three-yard touchdown to Kelvin Benjamin in the final minute and two interceptions.

'We didn't get the job done'

The highlight for Allen was a 57-yard pass to Zay Jones in the final two minutes of the first half. Unfortunately, a false start by tackle Dion Dawkins and Allen being sacked for an eight-yard loss on third down led to Buffalo settling for Stephen Hauschka hitting a 40-yard field goal.

"I'm playing this game to win football games and that's the only reason I'm playing," Allen said. "At the end of the day, we didn't get the job done, and I've got to do my part and I've got to be better."

The Bills traded up five spots to select the Wyoming product with No. 7 pick — the highest in the draft order the Bills have chosen a quarterback.

Allen started in place of Nathan Peterman, who managed just one first down, had 24 yards passing and threw two interceptions in 10 series against Baltimore.