Frias threw a bullpen session Monday and is an option to start Friday against the Pirates, Ken Gurnick of MLB.com reports.

EDGE Analysis

The Dodgers' fifth rotation spot is up in the air now that Mike Bolsinger has lost the job. The bullpen session is not normal for relief pitchers, so it would make sense that Frias, called up Sunday, would slide into that spot. He posted a 4.06 ERA in 77.2 innings last year but struggled to miss bats, as he struck out just 43 batters (5.0 K/9).