CLEARWATER, Fla. — After scrapping its way through Tuesday night’s opening round with a committee of pitchers, then earning a day off Wednesday, Tulane appeared to have the table ideally set for the rest of the American Athletic Conference tournament.

But its plans were upended in one fell swat Thursday.

Houston designated hitter Joe Davis’ third-inning grand slam off Tulane ace Emerson Gibbs propelled the fifth-seeded Cougars to a 5-3 triumph, sending the top-seeded Green Wave to the losers’ bracket at Bright House Field.

If Tulane (38-18) tops No. 8 seed UCF, its victim Tuesday, in an elimination game at 10 a.m. Friday, it would have to win two in a row against the Cougars for the second consecutive weekend to earn a spot in Sunday’s 11 a.m. final.

In last weekend’s series in Houston (35-22), the Green Wave rallied from a 13-inning loss Friday with back-to-back victories to claim the conference regular season title.

“We had the same situation last weekend where we lost the first game and we had to come back and win twice, so it’s definitely possible,” said shortstop Stephen Alemais, who drove in two of his team’s three runs Thursday.

“We’re not gonna give up. We have a lot of confidence in our team, and we’ve just got to worry about tomorrow’s game (against UCF) and move on from there.”

Davis’ blast, on an 0-2 curveball, was set up by Gibbs’ momentary lack of command. He allowed a leadoff single to Houston No. 8 batter Justin Montemayor, then walked shortstop Jose Reyes, a .214 hitter entering the game. After Zac Taylor’s sacrifice bunt, Gibbs walked right fielder Connor Wong.

“The problem was that we didn’t pitch to the nine-hole,” said Tulane coach David Pierce, whose staff has allowed a conference-low 17 homers this season. “We walked (Reyes) trying to give us an out. We didn’t execute in the bottom of their order to set that up.”

Alemais, who had given Tulane a 1-0 lead with a two-out RBI-double in the top of the third, cut Houston’s lead to 4-2 with a two-out RBI single in the fifth.

Two innings later, pinch hitter Matt Rowland’s two-out single scored catcher Jake Rogers — who had led off with a single — and chased Houston starter Seth Romero (6-4). One of the nation’s premier left-handers, Romero’s 11 strikeouts established a new AAC tournament record.

His closer, Nick Hernandez, allowed one hit over the final 2.1 innings for his 10th save. The Cougars, who moved to 30-0 when leading after the seventh inning, tacked on an insurance run in the bottom of the eighth.

“(Romero’s) just tough to score on. The closer’s up to 93-94 (mph), and he’s good too,” Pierce said. “They can really pitch and we’ve just got to get locked in a little bit better and figure out how to score.

“We’re just gonna come back and we’re gonna play one game at a time, one pitch at a time and do everything we can to give ourselves the best chance to come back and win.”