The 6-foot 11 inch (2.11 m) forward came to the Gonzaga Bulldogs in 2004 after a high school career in Clarkston, Washington that saw him named the state's Class 3A Player of the Year for three consecutive years. He sat out the 2004–05 season as a redshirt. Coach Mark Few and the Bulldogs counted on Heytvelt to be a major contributor in his freshman season of eligibility in 2005–06[2] as part of the supporting cast behind superstar Adam Morrison, but he missed most of the season due to a broken ankle suffered in the Maui Invitational.
In the 2006–07 season, he emerged as a potential star, becoming the team's second-leading scorer with 15.5 per game (behind Derek Raivio), top rebounder (7.7 per game), and leading shot-blocker (1.7 per game).[3] The best game of his career came on February 26, 2009 against Santa Clara, when he scored 29 points and grabbed 9 rebounds. However, in what was effectively his freshman year as a player, there were several games in which he made only sporadic impact.[2]
In May 2010, he signed with Lottomatica Roma until the end of the 2009–10 season and then was re-signed for another season,[5] but left the team in January 2011.[6] On January 13, 2011 he signed with KK Zagreb in Croatia until the end of the season.[7] He later re-signed with Zagreb for one more season.