Denver Broncos quarterback Drew Lock got his first professional win Sunday as the team defeated the Los Angeles Chargers with help from a late pass inference penalty and a game-winning field goal.

Lock was 18-for-28 with 134 passing yards, two touchdown passes and an interception. The rookie out of Missouri said after the game he was surprised with the late pass interference call.

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“That was my first time ever really seeing that flag get enforced,” he said of the call which is a spot foul in the NFL. “Most of the time in college football, that’s 10, 15 yards. I was like, 'Wait, the ball’s up there? We have a chance to win now.'"

Brandon McManus hit a 53-yard field goal to give Lock and the Broncos the win.

While Denver celebrated the call and the victory, Chargers players were left unsatisfied.

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“We were on the bench sitting like, ‘What the heck just happened?’ It was a blindside,” Chargers running back Austin Ekeler said, according to the Denver Post. “I was looking at the guys like, ‘We just lost the game?’”

Anthony Lynn said he asked for an explanation from the officials about why the flag was thrown.

“The explanation is that we made contact with the receiver too soon,” he said. “I didn’t see it that way.”

Chargers cornerback Casey Hayward, who received the penalty, said he thought the ball was uncatchable.

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“I thought it was a no-call, thought the ball was uncatchable and thought I was trying to find the ball myself,” he said. “I think I’ve got the same rights to the ball as he (does), but he made the call and we’ll live with it. He ran into me. I had my ground and I tried to look and find the ball.”

Denver improved to 4-8 with the win. Los Angeles fell to 4-8.