Las Vegas Raiders Aidan O’Connell, who had only recently ascended to starting quarterback, is headed to injured reserve with a fractured right thumb, ESPN and NFL Network reported Monday.

He’s expected to miss 4 to 6 weeks with a chance to return this season. ESPN reported O’Connell will get a second opinion on Monday. He was injured in Sunday’s 20-15 loss to the Los Angeles Rams.

O’Connell was named QB1 on Oct. 9, supplanting Gardner Minshew II, who won the job in the preseason.

O’Connell’s throwing hand was hit by Rams safety Kamren Curl, who was blitzing on a pass attempt in the first quarter. O’Connell was replaced by Minshew to begin a Raiders drive with 2:33 remaining in the period.

O’Connell was 6-of-10 passing for 52 yards in the early going against the Rams. He took over the starting spot from Minshew in Week 6 and entered after completing 63.9 percent of his passes for 403 yards with two touchdowns and two interceptions in three games (one start).

Minshew, 28, started the first five games, completing 70.7 percent of his passes for 1,014 yards, four TDs and five interceptions.

The Raiders (2-5) host the undefeated Kansas City Chiefs in Week 8.