Painter’s coaching career began in 1993 as an assistant at Washington and Jefferson College. After spending one year there, he moved on to Barton College where he also spent just one season. His next stop was at Eastern Illinois as an assistant coach. Painter spent three years at EIU before joining former Purdue assistant, and current Illinois head coach, Bruce Weber at Southern Illinois. He served as Weber’s right hand man for five seasons, and when his former coach left for Illinois, Painter was hired to replace him. In his lone year as the Salukis head coach his team went 25-5 and received an invitation to participate in the NCAA tournament. Though they lost a heartbreaking one point game to Alabama in the first round, Painter was regarded as one of the best young coaching prospects in the country.
His alma mater certainly took notice. The Boilermakers hired him as the eventual successor to Keady, inking Painter to a six-year contract. He spent the 2004-05 season as Associate Head Coach, shadowing Keady and hitting the recruiting trail hard. He became the head man the next season, but with just seven scholarship players, Purdue finished with a 9-19 record. The Boilers were much improved the following season, finishing with a 22-12 record and a second round NCAA tournament appearance (the team eventually lost to an Ohio State squad led by Lawrence North products Greg Oden and Mike Conley Jr.).
In 2008 Painter unveiled the most heralded recruiting class in the history of the program. Headlined by East Chicago’s E’Twaun Moore, Valparaiso’s Robbie Hummel, and Franklin Central’s JaJuan Johnson, the “Baby Boilers” went 25-9 in 2008 (earning Painter Big Ten Coach of the Year honors), and then went 27-10 in 2009, including a run to the NCAA Sweet Sixteen.
Purdue entered the 2009-10 season ranked 7th in both the Associated Press and Coaches Polls, the highest the Boilers have been ranked coming into a season in 22 years.