The Washington Nationals and right-handed reliever Craig Stammen have reached a two-year, $2.25 million extension agreement to avoid arbitration, according to Adam Kilgore of The Washington Post.

Craig Stammen's two-year deal is worth $2.25 million total, source says.

— Adam Kilgore (@AdamKilgoreWP) January 18, 2013

The Nationals selected Stammen in the 12th round of the 2005 MLB Draft. The right-hander came up through Washington's system as a starting pitcher, but after struggling in that role at the major league level he was converted to a reliever.

Stammen showed promise out of the Nationals' bullpen over seven appearances spanning 10 1/3 innings in 2011. During that time he allowed only one earned run on three hits with four walks and 12 strikeouts.

The 25-year-old followed this impressive stint with a sustained performance last season, maintaining an ERA of 2.34 over 59 appearances spanning 88 1/3 innings. Over that time he allowed 70 hits while registering 8.9 strikeouts to 3.7 walks per nine innings.