Bhuvneshwar Kumar kept his nerve with the final ball as Sunrisers Hyderabad beat Royal Challengers Bangalore by four runs on Wednesday in the Indian Premier League.
Kumar clinched the victory for his side after defending six runs off the final ball against AB de Villiers in a low-scoring thriller at the Sheikh Zayed Stadium in Abu Dhabi.
RCB looked on course for an easy win as Glenn Maxwell smashed 40 off 25 balls after captain Kohli (5) and Dan Christian (1) failed with the bat chasing a target of 142.
But Williamson's brilliant direct hit caught Maxwell out of the crease before Kumar and Jason Holder made a strong comeback, bowling the two last overs for 13 runs.
Devdutt Padikkal scored 41 off 52 balls and Shahbaz Ahmed contributed a quick 14 off 9 balls.
But Kumar (1-25) held his nerve in the final over against De Villiers, who ended unbeaten on 19, and George Garton.
Sunrisers batted first after losing the toss but made a shaky start with Abhishek Sharma (13) losing his wicket to Garton in the second over.
Priyam Garg scored 15 off 11, Wriddhiman Saha 10 off 8 and Holder made a brisk 16 off 13 balls.
Harshal Patel finished with bowling figures of 3-33.
Chennai Super Kings will face Punjab Kings and Kolkata Knight Riders will take on Rajasthan Royals on Thursday.
The top four teams will go through to the play-offs from Sunday.