[1] Haren starred for the baseball teams at Bishop Amat High School and Pepperdine University before the Cardinals selected him in the second round of the 2001 MLB draft.

After appearing in two more All-Star Games in 2008 and 2009, the Diamondbacks traded him to the Angels during the 2010 season for Joe Saunders and pitching prospects.

[2] Although he was never a particularly well-known player, Haren finished his career with three All Star game appearances and the seventh best strikeout-to-walk ratio in major league history.

[5] After he graduated from Bishop Amat, Haren enrolled at Pepperdine University in Malibu, California, on a college baseball scholarship.

Playing for the Pepperdine Waves baseball team, he was selected as West Coast Conference (WCC) Freshman of the Year in 1999.

He was the starting pitcher against the San Francisco Giants and allowed four runs (two earned) in six innings to pick up the loss.

He recorded his first Major League win with a six-inning start where he allowed only one run against the Los Angeles Dodgers on July 19.

He received a late-season call-up, and made five appearances in the postseason for the Cardinals, including two in the World Series.

The Cardinals were swept by the Boston Red Sox, but Haren pitched well, tossing 42⁄3 scoreless innings.

After the 2004 season, the Cardinals traded Haren in a package that included right-handed reliever Kiko Calero and top hitting prospect Daric Barton to the Oakland Athletics for Mark Mulder.

[11] On December 14, 2007, Haren was traded to the Arizona Diamondbacks, along with Connor Robertson, for prospects including Carlos González, Brett Anderson, Aaron Cunningham, Greg Smith, Dana Eveland, and Chris Carter.

[12] In his first season with the Diamondbacks he was selected to the 2008 All-Star game at Yankee Stadium along with his teammate, Brandon Webb.

Haren finished the year with a record of 14–10, 3.14 ERA, and 223 strikeouts in 229+1⁄3 innings, throwing three complete games in 33 starts.

He struck out 192 in 238+1⁄3 innings and led the American League with a 5.82 strikeout to walk ratio, while throwing a career high four complete games (three shutouts).

[20] After his June 22, 2013, start against the Colorado Rockies, Haren owned a major league-worst 6.15 ERA amongst qualified starters.

[30] On December 10, 2014, the Dodgers traded Haren, Dee Gordon, and Miguel Rojas, to the Miami Marlins in exchange for Andrew Heaney, Chris Hatcher, Austin Barnes, and Enrique Hernández.

[33] On July 31, 2015, the Marlins traded Haren to the Chicago Cubs for minor leaguers Elliot Soto and Ivan Pineyro.

[36] Haren usually had a slow pitching delivery, highlighted by a slight pause in the middle of his windup, that he sped up with runners on base.

[30] In December 2016, the Diamondbacks hired Haren as a special pitching assistant, applying sabermetrics and other baseball analytics.