lsugrambling.040517 HS 949.jpg

LSU undergraduate assistant coach Sean Ochinko celebrates with LSU shortstop Kramer Robertson (3) after Robertson's two run home run in the sixth inning against Grambling, Tuesday, April 4, 2017, at LSU's Alex Box Stadium in Baton Rouge, La.

Advocate staff photo by HILARY SCHEINUK

The LSU lineup roared to life Tuesday in a 13-2 romp against visiting Grambling.

The Tigers pounded out 15 hits — six of them for extra bases — and 10 LSU relievers combined to keep Grambling scoreless over the final eight innings.

Nine LSU players collected hits, and five of them collected multiple base hits.

“It was nice to see them start to swing the bat with some aggressiveness and confidence,” LSU coach Paul Mainieri said.

But Tuesday night's game at Alex Box Stadium didn’t always look like it was headed for a blowout. LSU (20-10) scratched and clawed its way to a 4-2 lead through the first 5½ innings Tuesday, failing to capitalize on a couple chances to break the game open.

After falling in a 2-0 hole after the top of the first inning, LSU chopped the deficit in half on a Kramer Robertson RBI single. LSU had runners at second and third with one out in the but was not able to strike for another run in the inning.

LSU then loaded the bases with nobody out in the second inning and brought the top three hitters to the plate. Again, the Tigers came up empty.

“We left it seemed like a small army at third base with less than two outs,” Mainieri said.

But in the sixth, the floodgates opened. The LSU offense, thirsty for a big performance, finally got one.

“We went up there and had fun, and it showed us what we can do when we have fun instead of being stressed out the whole time,” said freshman outfielder Zach Watson, who went 3 for 3 Tuesday. “The first three innings, you could tell we were stressed. We were trying to do too much.”

The Tigers hammered three different Grambling pitchers during a seven-run sixth inning that pushed them out to a comfortable 11-2 lead.

The seven runs scored by LSU in that inning were more than it scored in any of its five losses the past two weeks. The seven runs came on seven hits, which matched LSU's hit total in those five losses.

It started when Watson mashed a two-run home run over the bleachers in left field with one out. Watson finished the night a double shy of the cycle, and his long home run started a string of seven consecutive hits for LSU.

Two batters after Watson’s homer, Robertson also clubbed a two-run shot over the bleachers in left field. The no-doubter was Robertson’s fourth home run of the season and third in as many games. His previous season high was two home runs.

The last big lick of the inning came off the bat of freshman Rankin Woley, who went the opposite way with a double that scored Jordan Romero and Greg Deichmann to make it 10-2.

Bryce Adams hit a two-run shot in the seventh inning — in his first at-bat since March 15 — to provide the final score.

After the rocky start by freshman Todd Peterson, LSU’s 10 relief pitchers combined to keep Grambling (9-19) off the scoreboard. Those 10 pitchers combined to strike out nine batters, issued just two walks and allowed four hits over the final eight innings.

“They all did a pretty good job. ... We needed to get all those guys out there and it worked out pretty well for us tonight,” Mainieri said.

The Tigers hit the road for a weekend series against Arkansas that begins at 6:30 p.m. Friday. The Razorbacks sit atop the Southeastern Conference Western Division standings.

Though Grambling did not possess the type of pitchers LSU will see this weekend, Robertson said he thinks Tuesday’s big performance can still carry over.

“Absolutely. I think you can carry the momentum from a 15-hit game into this weekend and feel good about yourself, absolutely,” Robertson said. “If we got out here and got four or five hits and just scratched by, I don’t think we’d feel much better. But getting 15 hits in the game and hitting balls hard is a good feeling.”

Follow Luke Johnson on Twitter, @ByLukeJohnson.