The NBA has granted the Rockets a disabled player salary exception in the wake of Yao Ming's season-ending injury.

Yao underwent surgery on Jan. 6 to repair a stress fracture in his left ankle.

The exception allows Houston to acquire a free agent, or trade for a player without having to match salaries, up to the value of the mid-level exception (about $5.765 million).

The Rockets must use the exception by Jan. 31 or it will expire.

Houston was granted the same exception after Yao missed last season following re-constructive foot surgery.