SAN DIEGO — Keenan Allen was placed on season-ending injured reserve.

Rookie Joey Bosa was activated, with no real target date for when he’ll make his NFL debut.

And coach Mike McCoy had no real answers — or at least ones he wanted to make public — about why the San Diego Chargers collapsed in a 33-27 overtime loss at Kansas City on Sunday.

It was far from the start needed by the Chargers, who on Nov. 8 will ask voters to approve an increase in the hotel tax to help raise $1.1 billion to build a new stadium downtown.

They lost Allen to a suspected torn right ACL in the first half, when they looked like world-beaters rather than the team that flopped at 4-12 last year. It’s a particularly tough injury, considering that Allen missed the final eight games of 2015 with a lacerated kidney suffered making a spectacular touchdown catch.

Then they lost the game after leading by 21 points in the third quarter.

A lot of things went wrong for the Chargers after they looked so good in the first half. Melvin Gordon scored his first two NFL touchdowns as he looks to bounce back from a miserable rookie season. But then the Chargers went away from him in the second half.

There were two major breakdowns in the kicking game.

McCoy had Josh Lambo try a 54-yard field goal on fourth-and-2 while up 27-10 earlier in the fourth quarter. He missed, giving the Chiefs great field position to start their comeback. Rookie Drew Kaser punted just 17 yards in the final minutes of regulation, setting up the Chiefs for the tying score. The Chiefs won the overtime coin flip and marched down to the winning run by quarterback Alex Smith, who went to high school in the San Diego area.

McCoy pinned the entire thing on “a lack of execution.”

Was it also a lack of killer instinct?

“I wouldn’t say that it’s a lack of killer instinct. I would say it was a lack of execution in the fourth quarter in all three phases,” McCoy said. “They out-executed us and they performed at the end of the game better than we did. It was not a lack of focus at all.”

The Chargers also blew a 21-point lead in losing McCoy’s debut as Chargers coach in 2013.

Sunday’s loss was their ninth straight in the AFC West dating to 2014.

Bosa has been on the roster-exempt list. He missed all of training camp in a nasty contract dispute and then tweaked a hamstring last week. McCoy said he doesn’t know when Bosa will be ready to play.

“I can’t tell you if it’s going to be Wednesday he’ll be out there, is it going to be Thursday? I don’t know that right now,” McCoy said. “He’s got to do certain things to get on the field. We’ve also got to also be smart with it so we’ve got him for the long haul. We’ve got to make sure we do it the right way so when he’s out there he can help our team and play 60 minutes of football. Or as many snaps as we want him to.”

The Chargers host Jacksonville (0-1) on Sunday.


Follow Bernie Wilson on Twitter at http://twitter.com/berniewilson


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