Updated

WASHINGTON (AP) — Nationals right-hander Jason Marquis (mar-KEE) is expected to miss six weeks with a right elbow injury.

Marquis, who is 0-3 with a 20.52 ERA this season, got a second opinion Thursday that confirmed the original diagnosis of swelling and what the team said are "loose bodies" in the elbow.

He went on the 15-day disabled list Wednesday. The Nationals are going to bring up right-hander Luis Atilano from Triple-A Syracuse to replace Marquis as the scheduled starter Friday night against the Los Angeles Dodgers.

Marquis had a cortisone shot Thursday and will not throw for seven to 10 days, then will begin a throwing program.