Major league career
Though he started the 2001 season with the Triple-A Salt Lake Stingers,Shields was called up to MLB on May 25,making his debut against Tampa Bay Rays on May 26,pitching one-plus innings and allowing one hit and one walk. He was optioned back to Salt Lake,but was recalled on June 27. In eight relief appearances with the Angels,Shields allowed eight hits and seven walks before being optioned back to Salt Lake,where he stayed for the remainder of the season.
Though he began 2002 with the Stingers,Shields was recalled to the major leagues on June 14,this time for good. In his final 38 relief appearances,he allowed only seven earned runs,only allowing opponents a .176 average,the best in the league. He also started for the club on September 27 against the Seattle Mariners,receiving a no-decision and allowing four hits and two earned runs while striking out two.
Shields was a fixture in the Angels bullpen after the 2002 campaign. He was a member of the 2002 World Series Championship team,but did not fare well in the postseason—he allowed 2 home runs in 12⁄3 innings in Game 5 of the Series, his only appearance in the playoffs that year.
Shields began 2003, his first full year in the majors, in the bullpen. He posted a 1.68 ERA, working at least three innings twelve times. He led the American League with 69.2 innings of relief before moving into the Angels' starting rotation to end the season in August. As a starter, Shields was 4-6 with a 3.89 ERA, pitching at least seven innings in six of his thirteen starts. He ended the season with a 5-6 record and a 2.85 ERA.
For the 2004 campaign, Shields returned to the Angels bullpen. He pitched 22 consecutive shutout innings from May 9 to June 11, and worked three scoreless innings five times during the season. With fellow reliever Francisco Rodríguez, he was part of the first pair of relievers to post 100 strikeouts in one season since 1997, and was third in the American League in strikeouts with 109. In the post-season that year, he struggled in two appearances during the ALDS, pitching three innings and allowing two earned runs with a 6.00 ERA.
When Rodríguez replaced veteran Troy Percival as the Angels' closer in 2005, Shields emerged as the club's trusted setup man, pitching the eighth inning as the bridge to Francisco. In this capacity, he led the American League with 91.2 innings of relief pitching, and ranked second with 98 strikeouts and 32 holds. When Francisco was placed on the disabled list from May 15 to May 31, Shields stood in as the club's closer, earning five saves in six save opportunities. Overall, Shields posted a 10-11 record with a 2.75 ERA.
Shields represented the United States in the 2006 World Baseball Classic, the only member of the Angels to play for the USA squad. Shields finished the 2006 season with a 7-7 record, an ERA of 2.87 and 84 strikeouts. He led the league in holds with 31, and was second among American League relief pitchers in innings pitched with 87.2 innings.
Shields' 2007 season saw his ERA rise to 3.86 as he also failed to surpass 80 innings. He finished 4-5 in 71 games.
In 2008, Shields had a career low 2.70 ERA in 64 games.
Early in the 2009 season, he had to receive surgery on his left leg which forced him onto the disabled list for the remainder of the season. He finished with only 20 appearances on the season.
Shields was the team's setup man for the Angels prior to his surgery, holding the lead if necessary in the 8th and sometimes both 7th and 8th innings until the Angels go to closer Brian Fuentes.
After the surgery, Shields was not the same for the 2010 season. He pitched in 43 games while also starting a game for the first time since 2003. His ERA rose to 5.28 while also walking 34 in only 46 innings. His control issues were due to the injury he sustained in the previous year.
Shields retired after the end of the 2010 season. [2] In 2011, he was named by Sports Illustrated as the "Setup Man of the Decade." [3]
