LAFAYETTE — About the only discernible difference between dueling aces Gunner Leger and Lucas Humpal was the fourth inning Friday night at M.L. “Tigue” Moore Field.

Louisiana-Lafayette’s Leger struck out the Texas State side with a flurry of untouchable changeups, while Texas State’s Humpal gave up a decisive three-run double to freshman designated hitter Dylon Poncho, paving the way for the Cajuns to take the series opener 5-1.

“Right there, a true freshman went up against a very, very good arm and stuck a ball in the gap for us,” Cajuns coach Tony Robichaux said. “And I think that was the difference in the game.’”

Poncho’s three-run double gave the Cajuns (26-12, 11-5 Sun Belt) a 4-1 lead, and Leger (5-2) had already settled into a groove.

The only run the Bobcats (21-18, 9-7) mustered came when third baseman Jaylen Hubbard clobbered an elevated fastball well over the wall in left field. The ball caromed off the upper third of one of the giant pines behind the wall.

But Leger didn’t let that get to him. After Hubbard’s home run, the sophomore left-hander retired the next 12 Texas State batters, seven of them by strikeout.

His weapon of choice was his changeup, a pitch that moves down and away from a right-handed batter that was especially handy on a night when Texas State’s lineup featured eight righties.

“To the naked eye, you look at that and go, ‘Oh boy, it’s going to be a long night for a lefty,’ ” Robichaux said. “But not for changeup artists.”

Leger was truly artistic with his changeup Friday. After giving up the home run to Hubbard, he might have thrown it as often as he threw his fastball, especially when he struck out the side in the fourth.

Leger said he felt like he threw 15 changeups in that inning. He got Tanner Hill and Theodore Hoffman, the No. 3 and 4 hitters, to swing and miss over strike-three changeups.

“I’ve been struggling a little bit with my changeup, and that’s usually my go-to pitch,” Leger said. “Throughout the whole year really, I’ve been struggling with it. I adjusted my grip a little bit, and it started working tonight.”

Leger finished the night throwing a season-high 106 pitches in 6.2 innings. He matched his career high in strikeouts with nine.

Humpal (5-3) matched Leger through three innings, giving up a laser home run of his own to Steven Sensley, who demolished an opposite-field shot that clanged off the scoreboard just above the inning markers.

But the Cajuns got to Humpal in the fourth. Kyle Clement started the rally with a one-out single, then Stefan Trosclair legged out an infield single. Humpal hit Sensley to load the bases for Poncho.

“Through the whole at-bat, I was just staying calm and looking for my pitch to drive into the gap,” Poncho said. “He left one up and in, and I did what I had to do with the pitch.”

He yanked a 2-2 fastball into the left-center gap to clear the bases. Friday was only Poncho’s second start since March 26.

“Sometimes you have to play a small part in a big deal,” Robichaux said.

As they have done regularly as of late, relievers Eric Carter and Dylan Moore slammed the door, allowing just one runner in the final 2.1 innings.

Looking to clinch the series win at 6 p.m. Saturday, the Cajuns will start right-hander Wyatt Marks (3-4, 5.20 ERA).