The Milwaukee Brewers selected Sarfate in the ninth round of the 2001 MLB Draft. In 2003, pitching for the Beloit Snappers in the Midwest League he was 12-2 with a 2.84 ERA in 26 starts, and 140 strikeouts in 139.2 innings. He made his MLB debut on September 3, 2006. Sarfate pitched in eight games for the Brewers, with a 4.32 earned run average, and 11 strikeouts in 8.1 innings.
Houston Astros
The Brewers traded Sarfate to the Houston Astros on September 11, 2007, for cash considerations. After beginning his professional career as a starter, Sarfate spent 2007 as a relief pitcher. He made seven relief appearances for Houston, and was 1-0 with a 1.08 ERA and 14 strikeouts in 8.1 innings.
Baltimore Orioles
On December 12, 2007, the Astros traded Sarfate along with designated hitter/left fielder Luke Scott, pitchers Matt Albers and Troy Patton, and third baseman Michael Costanzo to the Baltimore Orioles in exchange for shortstopMiguel Tejada. in 2009 Sarfate also began 2008 as a relief pitcher. On July 28, 2008, he was moved to the Orioles' starting rotation. He returned to the bullpen after just four starts, in which he went 0-2 while allowing 18 runs in just 15 innings. Overall, in 57 games he was 4-3 with a 4.74 ERA and 85 strikeouts in 79.2 innings. Sarfate began 2009 in the Orioles' bullpen, but was sent to the AAA Norfolk Tides in the International League in May after posting a 6.49 ERA in eight appearances. He was called up again in September, and pitched much better, posting a 3.48 ERA over 12 relief appearances. Overall, he was 0-1 in 20 relief appearances with a 5.09 ERA and 20 strikeouts in 23 innings. In 2010, Sarfate pitched at AAA Norfolk, where he was 2-2 with 20 saves and a 2.73 ERA in 47 games, as he struck out 72 batters in 56 innings. He was named an MiLB Organization All Star.
Hiroshima Toyo Carp
In 2011, Sarfate signed with the Hiroshima Toyo Carp of Japan's Central League. Sarfate quickly became one of the top closers in Japanese baseball. He was a 2011 All Star. In 2011 he was 1-3 with 35 saves and a 1.34 ERA in 57 games. In 2012 he was 2-5 with 9 saves and a 2.90 ERA in 47 games.
Saitama Seibu Lions
He spent one season with the Saitama Seibu Lions in 2013. Sarfate was 9-1 with 10 saves and a 1.87 ERA in 58 games.
Fukuoka SoftBank Hawks
In 2014, Sarfate joined the Fukuoka SoftBank Hawks, and got the final save of the 2014 Japan Series. He was a 2014 All Star. For the season he was 7-1 with 37 saves and a 1.05 ERA in 64 games. In 2015, Sarfate closed out the 2015 Japan Series as well, as the Hawks won their second championship in a row. For the season he was 5-1 with 41 saves and a 1.11 ERA in 65 games. During the 2016 season, Sarfate recorded 43 saves, a new record for most single-season saves in the Pacific League. He was named a 2016 All Star. For the season he was 0-7 with a 1.88 ERA in 64 games. On April 2, 2017, Sarfate recorded his 178th save in Japan, setting a new record for most saves by a foreign pitcher in Nippon Professional Baseball history. The record was previously held by Marc Kroon of the Yomiuri Giants. On July 4, 2017, Sarfate recorded his 200th save, becoming the sixth pitcher in NPB history to reach that threshold and the first foreign pitcher. On September 5, 2017, Sarfate earned his 47th save of the season, breaking the record for most single-season saves in Japanese baseball history. He finished the season leading the league with 54 saves, as he was 2-2 with a 1.09 ERA in 66 games. Sarfate earned two saves and a win in the 2017 Japan Series, and won the Japan Series Most Valuable Player Award. He won the Pacific League MVP. He also received the Matsutaro Shoriki Award, for the year's greatest contribution to Japanese professional baseball. Sarfate had season-ending surgery on his right hip in April 2018, after pitching six innings. He missed the 2019 season as well. His 234 career saves are fourth-most in NPB history.