Source: Matt Moore, CBS Sports 
Bulls point guard Derrick Rose suffered a right knee injury Friday night in Portland and did not return to the game. Rose injured the opposite leg from the one he torn the ACL on cutting to the basket. There was no contact on the knee, it simply buckled underneath him. He was able to walk to the other end of the court before being tended to on the sideline and eventually being carried to the locker room.
The Bulls announced after the game that Rose will have an MRI  Saturday.
— Isaac Ropp (@iropp) November 23, 2013