Mark Warkentin

Mark Warkentin (born November 14, 1979) is an American open water swimmer and swimming coach. After graduating from San Marcos High School in 1998, Warkentin attended the University of Southern California, from which he graduated in 2003 with a degree in communication. While a Trojan, he was a four-time All-American. He was also awarded USC's Willis Award as a freshman.

Warkentin qualified for the 2008 Summer Olympics in Beijing following his performance at the 2008 Open Water World Championships. In the lead-up to the Games he was noted by Time as one of its "100 Olympic Athletes To Watch." He is a two-time national champion in the open water 25-kilometer, the longest sanctioned race in the sport.