- Bats Left, Throws Left
- Height 6' 2", Weight 230 lb.
- School Indiana State University
- High School Kokomo High School
- Debut July 26, 2007
- Final Game October 2, 2015
- Born October 4, 1981 in Indianapolis, IN USA
Joe Thatcher went undrafted after a 4-8, 5.60 ERA senior season in college. He signed with the independent River City Rascals and played with them in 2004-2005. He was noticed by scouts at the Frontier League's all-star game in 2005 and he signed with the Milwaukee Brewers, finishing the season in the Brewers' chain.
On July 25, 2007, he was acquired by the San Diego Padres along with two others in a trade for Scott Linebrink. He was immediately brought up to the big leagues and made his major league debut the next day. He did well that first season, with a 2-2 record and a 1.29 ERA in 22 games, but in 2008, his ERA rose to 8.42 in 25 games, forcing him back to the minor leagues for a while. He went undefeated in both 2009 and 2010, going 1-0 both years with ERAs of 2.80 and 1.29 respectively. He began to be used as an extreme LOOGY at that time, for example pitching a mere 35 innings in 65 appearances in 2010, and would continue in that specialized role in future seasons. He was then limited to 18 appearances in 2011, pitching his first major league game in early August. In 2012, he was back to 55 appearances and recorded his first career save in a season during which he went 1-4, 3.41. He was off to an excellent start to his 2013 season, with a 2.10 RA and a 3-1 record after 50 games, when he was shipped to the Arizona Diamondbacks at the trading deadline on July 31st. However, the rest of the year was not as good for him, as his ERA rose to 6.75 in his 22 games for Arizona.
Thatcher started the 2014 season with the Diamondbacks and was 1-0,. 2.63 in 37 games when he was traded again on July 5th, this time heading to the Los Angeles Angels of Anaheim in return for two minor leaguers.