Trevor Siemian, who has done more than anyone could have asked for through three weeks, was knocked out of Sunday’s game with what Mike Florio of Pro Football Talk is reporting is an AC joint sprain on his non-throwing shoulder.

The severity of the injury is still unknown; Siemian will undergo an MRI on Monday.

Nicki Jhabvala of The Denver Post reported that Siemian was day to day.

Florio, though, talked to another source who said that “it won’t be a surprise if Siemian misses a game, maybe two, as the shoulder heals.”

With the way Paxton Lynch played in place of Siemian on Sunday, the smart move for Gary Kubiak and the Broncos may be to rest Siemian until he’s fully healthy. The smart move for Siemian will be to get back on the field as soon as possible; he knows his job is secure for only so long.

The Broncos have a tough matchup against the surging Atlanta Falcons, who just dominated Cam Newton and the Panthers behind a 300-yard performance from Julio Jones. After that, they’ll travel to San Diego to face the Chargers. If Lynch were able to come out of that stretch 2-0, the job might be his for good.