It was the second of two terrific shots by Hickey, who also hit a 15-foot jumper to give LSU a 67-66 lead with 16 seconds left. Mississippi State came right back with Trivante Bloodman's acrobatic layup to push the Bulldogs ahead 68-67 lead with 7.9 seconds left, but that just set up some more Hickey heroics.
LSU (12-7, 3-5 Southeastern Conference) trailed for nearly the entire game, including a 40-26 deficit at halftime. But the Tigers methodically came back in the second half. Hickey and Johnny O'Bryant led the Tigers with 12 points each.
Hickey scored seven of his 12 points in the final 46.7 seconds. He drove the length of the court on his final shot, and the 5-foot-11 sophomore made the short floater over a pair of defenders to win the game.
Mississippi State (7-13, 2-6) has now lost six straight. Gavin Ware led the Bulldogs with 14 points while Bloodman added 12.
It's been a great week for LSU, which also had an impressive victory over No. 17 Missouri on Wednesday. The Tigers didn't play as well on Saturday against the Bulldogs, but escaped Humphrey Coliseum with a victory despite shooting just 4 of 25 (16 percent) from 3-point range.
Mississippi State put together a nearly flawless first half, shooting 16 of 28 (57.1 percent) from the field, outrebounding LSU 20-18 and forcing 10 turnovers.
Ware, the 6-foot-9, 270-pound freshman, led the Bulldogs with 10 first-half points, making all five of his field goal attempts.
Meanwhile, LSU struggled, making just 9 of 33 shots (27.4 percent) in the first half.
But LSU slowly cut into Mississippi State's advantage in the second half, getting to the basket with ease on fast break opportunities. Hickey hit a 3-pointer — just LSU's third of the game — with 5:21 left and then Shavon Coleman followed with a short jumper to cut Mississippi State's lead to 60-58.
Johnny O'Bryant hit a pair of free throws to tie the game at 60 with 3:13 left, but Mississippi State responded with six straight points to take a 66-60 lead with 1:38 remaining.
Mississippi State could have had a bigger lead, but struggled badly at the free throw line. The Bulldogs made just 13 of 27 (48.1 percent) attempts, including an ugly 8 of 20 mark (40 percent) in the second half.
That came back to bite the Bulldogs in the final minutes. Hickey's 3-pointer pulled LSU within 66-65 with 46.7 seconds remaining, which served as the appetizer for his clutch shooting in the final 20 seconds.
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