Rahm becomes first Spaniard to win the U.S. Open
An emotional Rahm quickly dedicated the victory to his late compatriot Seve Ballesteros, the man who put Spain on the golfing map by winning five major titles before dying of brain cancer at age 54.
Rahm edged South African Oosthuizen in a wild battle of attrition that finally turned into a two-man race as several other contenders came unglued on the difficult back nine.
He shot 67 for a six-under-par 278 total, and was confirmed as the champion when Oosthuizen was unable to eagle the par-five 18th.