Perhaps the Buffalo Bills will remember Thursday night’s fourth quarter from AJ McCarron more than the three ugly quarters that came before it.

For three quarters on Thursday night, McCarron looked like he might be playing himself onto the roster bubble. He had 39 passing yards and two interceptions through three quarters. Then he got hot in the fourth quarter against the bottom of the Chicago Bears‘ defensive depth chart. He led four scoring drives in a comeback 28-27 win.

It wasn’t a pretty performance overall, and it was noteworthy that McCarron started and played the whole fourth preseason game. Most starters and key backups never see the field in the fourth preseason game. The assignment seems to show where McCarron is on the Bills’ depth chart.

AJ McCarron struggled badly for most of preseason finale

The Bills’ decision to start McCarron on Thursday night seemed to be a clear sign they’ll be choosing between Nathan Peterman and Josh Allen for the starting job Week 1. Bills coach Sean McDermott has been secretive about his QB plan so we don’t know for sure, but it’s a reasonable assumption McCarron entered Thursday as Buffalo’s third-string quarterback.

McCarron’s night couldn’t have been much worse through three quarters. He threw a bad pick-six early. After three quarters he was 5-of-18 for 39 yards and two interceptions. The Bills were down 27-3.

McCarron wasn’t playing with starters, and was under a lot of pressure without any starting-caliber receivers to throw to. Still, no matter the circumstance, five completions and 39 yards in three quarters of any football game is about as bad as it gets. At one point McCarron’s passer rating hit 0.0.

The fourth quarter was much better. He threw three touchdowns and ran for another. The final line was still ugly: 13-of-34 for 156 yards. But it could have been much worse.

McCarron entered training camp as favorite to start

McCarron has had a tough August.

He wasn’t too bad in the preseason opener, completing seven of 10 passes for 116 yards. Then he completed just three of six passes for 12 yards against the Cleveland Browns, and left that game with an injury after failing to lead the Bills to a first down in four possessions. There was a report he had a hairline fracture of his collarbone, but further tests showed no breaks.

Maybe the Bills wanted to use the fourth preseason game to see if McCarron was healthy before deciding on a starter for Week 1. It still appears to be either Peterman or Allen for the season opener.

If McCarron is the third quarterback, the Bills will have a decision to make. Perhaps they can trade him, though his struggles for most of Thursday’s preseason finale won’t help. They might also decide it’s worth it to carry three quarterbacks because they liked McCarron well enough this offseason to give him a two-year, $10 million deal. McCarron had built up a market for himself after years as the Cincinnati Bengals’ backup quarterback, though he didn’t cash in as big as some figured he might.

The Bills might excuse the first three-quarters of Thursday night’s performance as McCarron playing with a lot of guys who won’t make the 53-man roster, not long after suffering an injury that kept him out of the third preseason game. The offensive line didn’t do much to help him.

If McCarron’s roster spot is secure, he can thank a hot finish in the fourth quarter. Had his night ended after three quarters, it might have been a tougher decision.

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Frank Schwab is a writer for Yahoo Sports. Have a tip? Email him at shutdown.corner@yahoo.com or follow him on Twitter!
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