The Houston Rockets on Sunday called off their trade for Detroit Piston forward Sean Elliott after he failed to pass a physical.

Rocket Coach Rudy Tomjanovich would not say what part of the physical Elliott had failed.

The 6-foot-8 forward was traded Friday for forwards Robert Horry and Matt Bullard. He took a physical Saturday in Houston, then Rocket physician Bruce Moseley requested additional tests.

Elliott, who had knee surgery in high school, plays with braces on both knees. Last season, playing for the San Antonio Spurs, he sat out 12 games because of back problems. He sat out his last four games with the Pistons because of pneumonia.