NASHVILLE, Tenn. — Not even a lower-leg cramp could keep Ben Simmons from delivering a big performance Saturday night.

Simmons limped to the bench with just more than four minutes to play in the LSU men’s basketball team’s Southeastern Conference opener at Vanderbilt with his team hanging on to a five-point lead.

But he came back about a minute later and helped LSU pull off a 90-82 upset that the Tigers desperately needed to start a tough three-game stretch to begin conference play.

After going to the bench for a little rest, Simmons, who was booed loudly when he was introduced before the game, came back and hit a pair of free throws to push the Tigers’ lead to nine points at 77-68 with 2:18 left.

Just 37 seconds later, Simmons raced up the floor and fired a bounce pass down low to Craig Victor, who slammed the ball down for an 80-68 cushion at 1:41 — which just about sealed the deal for the Tigers.

“I thought Ben did a great job spreading the floor,” LSU coach Johnny Jones said. “He executed in some big spots, and he was poised in getting the ball to the guys.”

Simmons, who was 10-of-15 from the floor and 16-of-19 from the free-throw line, finished with 36 points, 14 rebounds and four assists. The 36-point effort was seven points shy of the career-high 43 he had Dec. 2 against North Florida.

But there was a lot more to the win for LSU (8-5, 1-0), which enjoyed a 40-29 edge in rebounds.

LSU got 23 points from Keith Hornsby — with 15 coming after halftime — and Victor, who played a huge game defensively in holding Vanderbilt’s All-SEC center Damian Jones to 12 points and four rebounds, had 11 points with nine coming in the pivotal second half.

LSU outscored Vanderbilt (8-5, 0-1 SEC) in the second half 56-47 after the Commodores held a slim 35-34 halftime lead. The Tigers stayed in the game with a solid defensive effort in the first half, holding one of the league’s top-shooting teams to 36.0 percent from the floor.

“The big difference in our defense in the first half was our communication,” Simmons said. “Everybody was talking on defense and being aggressive from the jump — and we played with a chip on our shoulder.”

“We approached this game a little differently,” Hornsby said when asked whether a meeting at midweek was a big factor in the outcome. “I think we had a better edge coming into this game. We came out with a different type of energy and were better prepared for this one.”

After a decent first half, the Tigers came out strong in the second half and built a five-point lead behind Hornsby and Simmons before the Commodores bounced back and took its last lead of the night on a 3-point shot by Wade Baldwin IV at 51-50 with 14:16 left.

LSU regained the lead on a Hornsby 3-pointer with 13:21 to play at 53-51 and remained in front for final 13½ minutes — pushing the advantage to as many as 13 points in the final minute.

“We did more of the same what we did in the first half,” coach Johnny Jones said when asked about his team’s 56-47 edge in the second half. “The big thing was we were able to grind for some of those shots and not settle for shots early in the possession.”