Lakers Star Nick Young ROLLIN' WITH IGGY ... After Thumb Surgery

Iggy Azalea was standing by her man Monday ... even when he couldn't ... escorting Lakers star Nick Young out of a medical building following surgery on his thumb. 

Besides his GF, Nick's parents were also there as he was wheeled into a waiting ride in L.A. -- after undergoing surgery to repair the torn radial collateral ligament in his right thumb. 

Despite the fact he'll be out for 8 weeks, we're told Young was still smiling on his way out of the surgical center ... possibly because he'll still be raking in paychecks from his new 4-year $21 million contract. 

That'll make ya feel better.