Yao underwent surgery on Jan. 6 to repair a stress fracture in his left ankle. The disabled player exception allows the Rockets to acquire a free agent, or trade for a player without having to match salaries, up to the value of the midlevel exception (about $5.765 million).
KRIV-TV first reported that the Rockets had been granted the exception. Houston must use it by Jan. 31 or it will expire.
The Rockets were granted the same exception after Yao missed last season following reconstructive foot surgery. Houston used that money (about $5.7 million) to sign swingman Trevor Ariza. Houston traded Ariza to New Orleans after one season as part of a four-team deal that brought Courtney Lee to the Rockets.
Ariza and the Hornets were playing the Rockets in Houston on Friday night. The Rockets are 17-22 and have lost six of their last seven.
Yao's contract expires after this season. The top overall draft pick in 2002, Yao missed only two games in his first three seasons before beginning to have injury problems in the 2005-06 season, mostly in his left foot.
He played in 77 regular-season games in 2008-09, but then sustained a hairline fracture in his foot during the playoffs that required complex surgery.
The Rockets carefully monitored his minutes coming into this season, but Yao was injured in his fifth game.