Free agent pitcher Jason Marquis has agreed to a two-year contract with the Washington Nationals, sources confirm. The deal is said to be worth $15 million, according to a league official.

Marquis, a 31-year-old veteran with 10 Major League seasons under his belt, helped guide the Rockies to the playoffs in 2009 in compiling a 15-13 record with a 4.04 ERA and 115 strikeouts.

He joins a rotation that registered a 5.02 team ERA and allowed opponents to hit .276 against them last season.

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