Patriots offensive coordinator Bill O’Brien has a lesser known title that figures to be equally as important this season: quarterbacks coach.

Based on Mac Jones’ performance in training camp and preseason, O’Brien has put Jones’ development back on track. Jones ran away with the Patriots’ starting job this summer. His backups, however, are another story.

The Pats claimed ex-Panthers quarterback Matt Corral off waivers last Thursday and re-signed Bailey Zappe to the practice squad after releasing him. At least nominally, Corral is Jones’ backup, though Zappe could be elevated from the practice squad to the game-day roster on Sunday and serve as the No. 2 for the Pats’ season opener.

On Tuesday, O’Brien pulled back the curtain on Corral’s onboarding process, which has also included assistant quarterbacks coach Evan Rothstein.

“Matt has been here morning, noon and night, and he’s doing a good job of learning,” O’Brien told reporters on a conference call. “And we just need to keep progressing him. You can’t throw everything at him at once because that’s a lot of information. So we try to do a good job of giving them the things that are important for him right now. And it’s a team effort, and he’s done a good job of just coming in here and trying to learn and soak it up.”

As for Zappe, O’Brien indicated he still sees potential in the second-year backup who was released last week after a disappointing preseason. Zappe also posted the highest interception percentage of all the Patriots’ quarterbacks in training camp.

“I know that Bailey’s improved. I’m really happy that he’s back with us,” O’Brien said. “Bailey’s a young player, as a lot of these guys are there. When you talk about a guy only going into a second year, there’s a lot of improvement that’s been made, and there’s a good future.

“And so, it’s really good that we have Bailey back. We can continue to work with him and he’s a good guy to work with. He works very hard.”