Daniel Dean Warthen
- Bats Both, Throws Left
- Height 6' 0", Weight 200 lb.
- High School Omaha North High School
- Debut May 18, 1975
- Final Game September 29, 1978
- Born December 1, 1952 in Omaha, NE USA
After his playing career ended, pitcher Dan Warthen went on to be pitching coach with the Seattle Mariners (1992), San Diego Padres (1996 and 1997), Detroit Tigers (1999-2002) and bullpen coach for the Los Angeles Dodgers (2006-2007).
He was the pitching coach for the St. Lucie Mets in 2003, the Norfolk Tides 2004-2005, and New Orleans Zephyrs 2008. On June 17, 2008, Warthen was called up to the majors to replace Rick Peterson as the New York Mets pitching coach. He stayed in the job until the end of the 2017 season. In 2018, he joined the Texas Rangers as assistant pitching coach, working with former pupil Doug Brocail, who was now the team's pitching coach.