WASHINGTON — Desperate for some semblance of pitching depth, the Phillies signed 35-year-old righthander Jason Marquis to a minor-league deal Tuesday.

Marquis, who has made 309 career starts in the majors, will report to extended spring training. He pitched for San Diego in 2013 and posted a 4.05 ERA in 20 starts.

The Phillies have used relievers in recent weeks to start games at double-A Reading and triple-A Lehigh Valley. Their current triple-A rotation is Greg Smith (30 years old), Sean O'Sullivan (26), Barry Enright (28), Brad Lincoln (29) and Chris Bootcheck (35).

Marquis underwent Tommy John surgery last July. He could serve as a rotation replacement later this season should the Phillies trade any of their current starters. A.J. Burnett, Kyle Kendrick and Roberto Hernandez could be free agents at season's end.

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