The Tigers (28-16, 7-12 SEC) snapped a four-game SEC losing streak, while the Razorbacks fell to 30-13 overall and 10-9 in conference play.
The series continues at 2 p.m. Saturday when freshman right-hander Louis Coleman (4-3, 4.58) takes the mound for LSU. He will be opposed by senior left-hander Trey Holloway (4-0, 4.40).
Saturday will also be Warren Morris Day at Alex Box Stadium as the hero of the 1996 College World Series will sign autographs and throw out the first pitch. Fans are encouraged to wear gold to the game.
Warren Morris Day comes one day after another Tiger infielder provided similar heroics Friday night. Hollander, who was hitless entering his final at-bat, connected for his first homer since March 18 at Kentucky.
"I was looking fastball and I don't think he (Arkansas pitcher Devin Collis) meant to throw it there," said Hollander. "It was a mistake and a little up in the zone. I have never done that before (hit a walk-off homer). That was definitely the biggest hit of my career here."
Hollander's blast was the first walk-off homer by a Tiger since Clay Harris hit one in a victory over Ole Miss on April 16, 2005.
"He just ran into one, and he was looking for something to drive," said head coach Smoke Laval. "I think he was really trying to stand tall and hit a double, but he hit it well."
Collis (5-1) suffered the loss, surrendering four hits and the game-winning homer in two innings of work.
Jonathan Wilhite (1-0) picked up win despite missing a save opportunity in the top of the ninth. The right-hander worked 1.1 innings, allowing two hits and a run.
Wilhite relieved junior southpaw Clay Dirks, who was in line for his first victory since March 10. Dirks scattered nine hits and five runs in 7.2 innings of work.
"Dirks took us late into the game and it was a good win," said Laval.
Meanwhile, Arkansas starter Nick Schmidt settled down after allowing a two-run homer to first baseman J.T. Wise in the first inning. Schmidt allowed four hits and six runs, walked five and struck out six.
Centerfielder Jake Dugger put the Hogs in front with a one-out solo homer off of Dirks in the first. However, LSU answered in its first at-bat.
Schmidt walked Hollander, and two batters later, Wise smashed a two-run homer into the left field seats to give LSU a 2-1 lead.
Wise's ninth blast of the season would be the last hit the Tigers would get until a Quinn Stewart single in the sixth.
Schmidt retired 10 straight batters following the two-run homer until he allowed a leadoff walk to designated hitter Jordan Mayer in the fifth. Mayer was erased on a fielder's choice by centerfielder Jarred Bogany.
Arkansas reclaimed the lead in its half of the fifth when the bottom of the order produced. Dirks issued a one-out single to catcher Brian Walker. Shortstop Matt Willard, the ninth man in the order, then unloaded a two-run homer down the left field line.
Arkansas held a 4-2 lead in the the seventh when LSU finally got to the southpaw. Schmidt walked Mayer, and Bogany extended his hitting streak to six games with a blooper to shallow center.
Third baseman Will Harris worked a one-out walk to load the bases. Laval then elected to pinch hit Robert Lara for second baseman Jason Ogata.
Lara did not disappoint as the true freshman fouled off a series of pitches before lining a clutch RBI single to left to pull the Tigers within a run at 4-3.
Right-hander Darryl Maday, who relieved Schmidt after Lara's single, walked in the tying run on a four-pitch at-bat to Hollander.
Left fielder Bruce Sprowl then greeted Collis -- the Hogs' third pitcher of the inning -- with the go-ahead single to center, scoring Harris.
Stewart provided an insurance run when he beat out a ground ball for a fielder's choice RBI that gave LSU a two-run cushion at 6-4.
First baseman Danny Hamblin trimmed the lead to 6-5 in the eighth with an RBI single, scoring second baseman James Ewing.
Ewing drove in the tying run with two outs in the top of the ninth after Wilhite plunked Willard and gave up a single to pinch-hitter Craig Gentry.
Collis returned to the mound in the ninth and fanned second baseman Nick Pontiff to start the frame. Hollander then took a first-pitch ball from Collis before connecting on his fourth homer of the season with a line-drive shot just inside the left field fair pole.
Hollander's walk off homer propels LSU
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