Jon Rauch went 4-8 with a 4.14 ERA (33 ER in 71 2/3 IP) and a career-high 18 saves in 74 games with the Arizona Diamondbacks and Washington Nationals after being acquired by Arizona on July 22 in exchange for infielder Emilio Bonifacio. He finished tied for sixth among National League relievers with 16 walks allowed and ninth with a 4.13 strikeout-to-walk ratio.
In his first dozen games with the Diamondbacks, Rauch was everything they hoped he would be. He held the opposition scoreless in 10 of those contests, racked up five Holds, and boasted a 14:1 strikeout-to-walk ratio.
Rauch then allowed an earned run in each of his next six outings, and finished his time with the Diamondbacks 0-6 with a 6.56 ERA. After walking just seven batters and allowing five homers in 48.3 innings with the Nats, he walked nine and allowed six in 23.3 frames with the D-backs.
His 2010 club option needed to be exercised within five days of the completed 2008 World Seires, or Rauch would have become a free agent at the end of the 2009 season. The Diamondbacks are likely losing both Juan Cruz and Brandon Lyon to free agency, so the club decided to take a gamble that Rauch is indeed the player we saw in the first four-and-a-half months of the season. He makes $2 million in 2009.
Rauch owns a 24-23 career record with a 3.83 ERA (145 ER in 341 IP) with 24 saves, 109 walks and 287 strikeouts. He has appeared in 281 games for the Chicago White Sox, Montreal Expos (Washington Nationals) and D-backs over parts of five seasons.