Bill O'Brien spent five years with the Patriots, including two as the quarterbacks coach (2009-10) and one as the offensive coordinator (2011). But what he may be most remembered for in New England is one particularly fiery sideline spat with Tom Brady.
It was a "Teapot" moment for the Texans coach, who will re-visit Gillette Stadium on Saturday for the Divisional Round of the playoffs. That's what Brady and backup Brian Hoyer nicknamed O'Brien for his quick temper, and it would be hard to imagine a moment when O'Brien was hotter than in the fourth quarter of a 2011 win over the Redskins.
The Patriots were up a touchdown and knocking on the door to score again when Brady was picked off in the end zone. When he got back to the sideline, Brady told intended receiver Tiquan Underwood that he had to make a better effort to come back to the football since he had been under-cut.
But when O'Brien saw Brady talking to Underwood, he unloaded. Perhaps it was because he didn't like Brady's throw. Perhaps it was because Brady missed Wes Welker for an easy touchdown on the play before, throwing behind his wide open slot receiver.
Either way, Brady and O'Brien then engaged in a shouting match that required Hoyer, receivers coach Chad O'Shea and head coach Bill Belichick to break it up.
"He kind of let me have it. I deserved it," Brady told WEEI's Kirk and Callahan show. "It was kind of a dumb throw. I deserved it. I kind of chirped back, and he didn't like it. I was kind of fiery at the time, too.
"We cooled off pretty quick. That's Billy's style. Billy's gonna let you know if he doesn't like something that you did. He handles it in the right way, in a way that you really respected. You know he's fiery, you know he just wants to get the job done. We cooled off. We ended up winning the game [when] Jerod Mayo made a great interception to end that game. By the time we got to the locker room we were good.
"There are a lot of emotions in this game. You wear them on your sleeve, and sometimes you just fire off. That's just the way it goes."
Brady said he remains friends with O'Brien and that they touch base from time to time. By putting in the "grunt work" of a lower-level assistant and quickly working his way up the coaching ranks in New England, O'Brien earned Brady's trust and respect.
Though he generally roots for O'Brien's success, that stops this week as the two prepare to face off later this week with their seasons on the line. It will be the second time O'Brien has been to Gillette Stadium this season with the Texans. Back in Week 3 they fell to the Patriots, 27-0, with rookie Jacoby Brissett getting the start at quarterback.
Brady said that Patriots players will have no problem getting themselves motivated for this one, though.
"This is a day-to-day league," he explained. "It really doesn't matter last time we played 'em or last year. Because things change so much with a game and a game plan and players. Coach talks about all the time it's not who you play, it's how you play, and we need to play well . . . "
"You put together the process and a winning formula, and then you go out and execute it. If you don't execute it, you lose. I don't think you take anything for granted, I don't think you mail in your preparation. I think we go about it the exact same way same way we've gone about it all year, which is we put teverything into it.
"We empty the tank in our practices which we always do, and then you come out at the end of the week with confidence and show everyone out there that we're prepared, and we can play because we're playing a really good team. We're playing a team that's earned this opportunity."