FAYETTEVILLE, Ark. — A Saturday that didn’t start well turned into something special after all for the LSU men’s basketball team.

Actually, it was extra special.

Needing a win at No. 18 Arkansas, which had lost just once on its home floor all season, LSU knew it was in for an uphill battle — especially with star forward Jordan Mickey sidelined by a shoulder injury.

But it turned out well.

First, LSU outplayed Arkansas for most of the afternoon and quieted a rowdy crowd of nearly 19,000 fans in Bud Walton Arena on Keith Hornsby’s clutch 3-point basket at the buzzer for an 81-78 victory that boosted its NCAA tournament résumé.

Then, seven hours later, the Tigers found out they had earned the No. 4 seed (and a double-bye into Friday’s quarterfinals) for the Southeastern Conference tournament, which begins Wednesday in Nashville, Tennessee.

Thanks to losses by Texas A&M earlier in the day and Ole Miss on Saturday night, LSU finished in a four-way tie for third place in the league and got the fourth seed for the tournament on a tiebreaker. But the second part couldn’t have happened without the first part, with the Tigers turning in one of their best performances of the season when they needed it most.

“We knew coming into the day, coming into this type of environment and atmosphere, we were going to have to play every second, every play against a great basketball team,” coach Johnny Jones said. “We knew it would take a great effort, and that’s exactly what it took for us today — playing every second of every play.”

That was true when Hornsby buried a 3-pointer from the corner, with the ball leaving his right hand with 1 second to go and landing in the net as the buzzer went off — drawing a collective gasp from the crowd.

That came after forward Jarell Martin, who had a game-high 27 points, made the defensive play of the game — blocking an Alandise Harris shot when he tried to get to the rim on a spin move with 25 seconds to go in a 78-78 tie.

Josh Gray, who delivered the ball to Hornsby for the game-winning shot, said he knew the Tigers were going to win — despite the long odds they faced all day — when they huddled during a timeout before the Razorbacks’ last possession.

LSU, after all, was on the cusp of an upset when it led for 32 minutes to only 5½ minutes for Arkansas.

“I told the guys in the timeout, ‘Man, we’re going to get one stop. … We’re going to dig deep and get a stop, and we’re going home with a bucket,’ ” said Gray, who had 10 points and six assists while turning the ball over just once against Arkansas’ pressure defense. “That’s what happened.”

Gray was just one of several players who made key contributions to help fill the void created by the absence of Mickey, who is averaging 16.0 points and 9.9 rebounds.

While they weren’t flashy, Darcy Malone, Brian Bridgewater and Aaron Epps combined for eight points and seven rebounds, with Epps scoring five of those points in a key four-minute stretch of the first half that allowed the Tigers to take a 41-35 halftime lead.

After Arkansas came alive in the final four minutes and took a slim lead with 3½ minutes left, LSU dug deep again and again to pull out the win that may have clinched an NCAA tournament bid.

“Aw, it was pretty tough,” Martin said of playing without Mickey. “We knew going into the game, like Coach Jones said, one of our primary players and one of the leaders on our team wasn’t going to play. It was really tough, but we played through each other out there.”

In the top 50

With the huge road win over a quality team, LSU moved back into the top 50 when the various RPI lists were updated Sunday.

The Tigers jumped to 48th in the NCAA.com, ESPN.com and CBSSports.com RPI after falling outside the top 50 with Wednesday’s loss to Tennessee.

ESPN.com bracketologist Joe Lunardi and CBSSports.com’s Jerry Palm had LSU as a No. 10 seed in the NCAA tournament. Lunardi had the Tigers in the East region going against No. 7 seed Iowa in Omaha, Nebraska; Palm had them in the Midwest region against No. 7 Wichita State in Louisville, Kentucky.

Follow Sheldon Mickles on Twitter @MicklesAdvocate.