One of Bill Belichick’s mantras is “next man up.”

The New England Patriots’ coach is living that reality in his team’s game against the Miami Dolphins.

With just under five minutes left in the first half and the Patriots cruising, 21-0, Garoppolo was hit by Kiko Alonso, who came in on Garoppolo’s blind side as he was releasing a pass for Malcolm Mitchell. Garoppolo landed on his elbow and then shoulder and was down for several minutes being tended to by the team’s medical staff. Coach Bill Belichick came onto the field and stood nearby while Garoppolo was checked out.

The third-year quarterback walked off the field and was taken directly to the locker room and for X-rays, the cameras capturing him visibly in pain. He didn’t return.

Garoppolo was 18-for-27 for 234 yards and three touchdowns with no interceptions.

Without Garoppolo, the Patriots turned to rookie Jacoby Brissett, who finished 6-of-9 for 92 yards. The Patriots held on to win, 31-24.

MassLive.com Patriots beat writer Kevin Duffy tweeted that Garoppolo’s x-rays were negative, while a second writer, Jeff Howe of the Boston Herald, tweeted that Garoppolo was still underdoing tests and will not play on Thursday night against the Houston Texans. A couple of minutes later, Howe cited a league source that said Garoppolo may be out for six weeks.

Predictably, when Belichick was asked about Garoppolo after the game, he said, “I don’t know yet so we’ll just take it day-to-day.”

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