After going unclaimed on waivers, former Red Sox pitcher Brad Penny signed a minor league contract with the Giants. He will be eligible for the Giants postseason roster.

Initially, no one claimed Penny because a claiming team would have been responsible for the remainder of his contract. The Giants only have to pay him the pro-rated portion of the big-league minimum of $400,000, which will be less than $100,000.

He joins NL Cy Young winner Tim Lincecum, Matt Cain, Barry Zito and Jonathan Sanchez in San Francisco's stacked rotation.

The Red Sox released Penny on Thursday after he went 7-8 with a 5.61 ERA this season. They signed him to a $5 million, one-year contract last year after he spent more than four seasons with the Dodgers.

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