Two early plays turned Tulane’s Halloween game against Cincinnati into a nightmare.

The rest of the first half became a full-scale horror show.

A promising opening drive ended when quarterback Tanner Lee was sacked right after he looked up after a play-action fake on fourth-and-goal from the 2-yard line. Three plays later, senior defensive end Tyler Gilbert drew a 15-yard personal foul penalty and was ejected for targeting on an incomplete pass that would have given Cincinnati third-and-10 from its 32.

Almost nothing went right from there for the Green Wave (2-6, 1-3 American Athletic), which fell behind 24-0 by halftime and lost 38-14 to Cincinnati (5-3, 3-1) at Yulman Stadium in a game televised by ESPN2. Not even three replay reversals in their favor — one that nullified a Bearcats touchdown and two that erased Tulane turnovers — made a difference.

The offense, which has had most of its success in the first quarter of games, needed that early touchdown. The Green Wave started fast in its previous three games at Yulman Stadium, scoring touchdowns on its first series against Georgia Tech and Connecticut and reaching the end zone on its second drive against Southeastern Louisiana.

This time, the Wave got no points on its eight first-half possessions, struggling to pick up tough yards against the 115th-ranked defense in the nation. Power back Lazedrick Thompson was stuffed for a 2-yard loss on third-and-1, ending one drive. Dante Butler came up 2 yards short on another third-down run, leading to another punt. And Lee’s fourth-and-goal sack came after Thompson went nowhere on third-and-goal from the 2.

“We have to score in those situations,” Tulane coach Curtis Johnson said. “That’s on me. I wanted to get it in the end zone and be aggressive.”

Tulane converted its first third-down opportunity, then failed on its next seven encompassing the rest of the half.

The defense was slow to adjust after losing Gilbert, who leads Wave linemen with 23 tackles and has a team-high three sacks. He ripped his helmet off in anger when the referee announced he was ejected, and Tulane appeared headless for the rest of the half.

“When Tyler Gilbert was ejected, our defense kind of wandered around a little bit,” Johnson said. “He’s one of our better players, so (defensive coordinator Lionel Washington) had to call the game a little different.”

With fellow starting defensive end Royce LaFrance playing sparingly in the first half — Johnson said the personal packages did not fit what he had practiced — the coaches tried an unusual three-man line of tackles with Tanzel Smart, Sean Wilson and Corey Redwine. Cincinnati promptly ripped off a 30-yard gain on a screen that set up a field goal.

Later in the first quarter, Bearcats running back Rod Moore rumbled 61 yards to set up a touchdown. Cincinnati also scored on a 54-yard pass play as the Wave failed to register a sack on quarterback Munchie Legaux and allowed 275 yards in the half and 9.5 yards per play while looking slow-footed.

Tulane had held its previous two opponents, UConn and Central Florida, to 217 and 233 yards for the entire game. Johnson said his defense would need to be just as sharp against Cincinnati’s prolific offense to give the Wave a chance to win.

Without Gilbert, it didn’t happen.

“He’s one of our senior leaders and one of our playmakers, but it was kind of forgotten after it happened,” safety Sam Scofield said. “We just gave up too many big plays and missed too many tackles tonight.”