SAN DIEGO — For Marcus Santos-Silva, the right hand proved to be the “right” hand Sunday night.

Texas Tech’s super-senior forward shot two perfect swishes from the free throw line to give the No. 3 Red Raiders a 55-52 lead over No. 11 Notre Dame with 54 seconds remaining — with his right hand.

Santos-Silva, a lefty, shot free throws with his left hand for much of the season before making a mid-season switch.

“I think he did that on his own about a month ago,” Mark Adams said. “He’s left-handed but he started shooting with his right hand.”

Santos-Silva shot just 46.3 percent on free throws going into Sunday, the worst mark of anyone on Texas Tech’s team with at least 15 attempts.

Sunday, he was a perfect two-for-two. His last game with a perfect free-throw shooting performance was January 22 against West Virginia.

Santos-Silva also made key plays on the defensive side of the ball to help the Red Raiders beat Notre Dame, including a block on Irish guard Blake Wesley on the possession before his free throws.

Santos-Silva and the Red Raiders will play No. 2 Duke in the Sweet 16 Thursday.