Jordan Romero watched his high school teammate Chris Sciambra throw the season’s ceremonial first pitch.

Sciambra’s walk-off home run in last season’s NCAA tournament super regional against Louisiana-Lafayette played on a loop while fans showered him with praise.

Romero, a backup catcher, sat in the dugout following the first inning of Friday’s 6-5, 12-inning win against Cincinnati. The friends talked, Sciambra recounting the home run in great detail to the fellow Catholic High School product.

“It was a ball,” Sciambra said. “Up.”

“Who cares?” Romero laughed back.

After his ninth-inning heroics forced the game into extra innings, Romero blooped David Orndorff’s full-count offering into short right field to score O’Neal Lochridge and seal the Tigers’ season-opening win Friday night in Alex Box Stadium.

“Kind of cool,” Romero said. “Mine was a ball. It wasn’t a home run, but it won us the game.”

Orndorff — Cincinnati’s fourth reliever of the night — balked Lochridge into scoring position in the 12th, the last in a long line of bullpen blunders for both teams in the 3-hour, 59-minute marathon.

Up with two outs in the ninth and his team trailing 3-2, Romero, pinch-hitting for shortstop Trey Dawson, took the first pitch of his college career back up the middle for a game-tying, two-out, RBI single that sent his teammates spilling onto the field in celebration and the winning run to third base as the lineup turned over.

Kramer Robertson bounced into a fielder’s choice to end the threat and send the game to extra innings — LSU’s 10th in its previous 38 regular-season games.

In a game when LSU twice was down to its last out and mustered a 4-for-23 clip with runners on base, it benefited from wobbly Bearcats pitching and a stout outing from junior Alden Cartwright, who got the win and steadied an otherwise-shaky bullpen performance.

After he issued a walk to Ryan Noda — the first batter he faced — Cartwright was marvelous, throwing two scoreless innings to breathe life into an otherwise lethargic stadium that saw most of its fans file out in the 10th inning.

Woody Wallace singled to open the 10th and Hunter Newman, in his third inning, issued consecutive walks to load the bases before being lifted in favor of Parker Bugg.

Manny Rodriguez greeted him with a rocket up the middle that scooted off Robertson’s glove and allowed the go-ahead run to score. Bugg walked Kyle Mottice two batters later to make the deficit 5-3.

Cincinnati’s bullpen took its turn imploding in the 10th, losing a two-run lead after three pitchers combined to hit three LSU batters — two with two outs — including Cole Freeman, who gleefully took one off the arm to drive in the tying run in the 10th after Brody Wofford’s single cut the deficit to 5-4.

“I’m really proud of our team because we came from behind a couple of times to tie the game,” coach Paul Mainieri said. “It all looked very bleak.”

Romero followed but couldn’t recreate his ninth-inning heroics, sending a popup on the infield that prolonged the game.

LSU starter Jared Poché was marvelous through six innings of one-run baseball, keeping his velocity in the lower 90s with a plus changeup. But he ran afoul in the seventh, surrendering three hits and two runs, the most damaging a two-run double from Treg Haberkorn that gave the Bearcats a 3-1 lead.

“We’ll take the victory,” Mainieri said. “Hard-fought win. We’ve got to sleep fast because we play again early tomorrow. I’m sure Cincinnati will come out and play their hearts out again tomorrow like they did today.”