One year after graduating from Wagner, he became the school's Head Baseball Coach. He would hold this job until 1986 when he became a full-time basketball assistant at Siena College under Mike Deane. When he became Wagner's basketball coach in 1989, he was the youngest Division I coach in both basketball (28) and baseball (23).
At Wagner, Capstraw had a 117-164 record and no NCAA Tournament or NIT bids. He was the 1993 Northeast Conference “Coach of the Year” and won the 2000 Metropolitan Basketball Writers “Good Guy Award”.
Capstraw's broadcasing career began with a three year stint as a television and radio analyst for the Northeast Conference. During the 2001-02 season he was a television analyst for the Atlantic 10 Conference. He joined the Nets Radio broadcasts in the 2002-03 NBA season. He has also filled in on YES Network's Nets telecasts.
In addition to his work on Nets broadcasts, Capstraw serves as NBA TV’s lead analyst for their Euroleague broadcasts and several other international championships, including the 2004 FIBA Diamond Ball Tournament, the 2003 EuroBasket tournament, and the 2003 FIBA Asia Championship. In 2006, he worked on NBA TV's coverage of the Las Vegas Summer League.