The Utah Jazz selected Ostertag with the 28th pick in the first round of the 1995 NBA draft. The Jazz hoped he could fill a void in the team's defense created by the retirement of Mark Eaton a few seasons earlier. Ostertag saw limited action in his rookie year, but emerged as Utah's starting center during his second season. The Jazz made back-to-back appearances in the NBA Finals in 1997 and 1998, with Ostertag providing strong defense in the playoffs against the likes of Hakeem Olajuwon, David Robinson, Tim Duncan, and Shaquille O'Neal.