A nice, cushy 16-point first-half lead was gone like a wisp of smoke, and Georgetown’s stay at the final Big East tournament appeared dangerously close to ending abruptly. Coach John Thompson III looked at his team, unusually flat for the first few possessions of the second half, and admitted later, “Yes, you worry.” Cincinnati, so discombobulated on offense for so long, had turned its deficit into a lead.

And then Thompson considered the players in front of him, his team.

“For the most part, this group doesn’t get rattled,” Thompson said.

After Thompson called a timeout, the Hoyas calmly assessed the situation, adjusted and ran away from Cincinnati in a Big East quarterfinal, posting a 62-43 victory at Madison Square Garden on Thursday afternoon that was well-rounded on offense and downright rugged on defense. Sophomore forward Otto Porter Jr., the conference’s player of the year, led the way with 18 points, including an 11-for-11 performance from the free throw line that put the game away.

But the Hoyas dispatched the Bearcats — and advanced to face fifth-seeded Syracuse in Friday’s semifinals — because when Cincinnati started pouring in three-pointers from anywhere over the half-court line, Georgetown responded with a variety of defenses that stifled Cincinnati — some zone, lots of half-court man-to-man, and even some full-court pressure.

Witness: Cashmere Wright’s fourth three-pointer of the game, then his floater in the lane, put the Bearcats up 33-31 less than four minutes into the second half. After that, Wright didn’t score another point, and the Hoyas went on the 11-2 run that put them in command for good. Sean Kilpatrick, the Bearcats’ leading scorer, made just 2 of 12 shots and missed all eight of his threes.

“We just made the proper adjustments,” Georgetown point guard Markel Starks said. “And then you just have to take pride in it. You have to say, ‘We’re not going to just let this guy get shots.’ It’s no formula. Everyone’s talking about our defense now, but we’ve been playing defense all year.”

They played it exceptionally Thursday, holding an offensively challenged Cincinnati team to 36.8 percent shooting, forcing the Bearcats to miss their final six three-pointers. Once the Hoyas (25-5) pushed the lead back to double digits, Cincinnati (22-11) never got it back under.

“We just had to not let it get to us,” Porter said.

The Georgetown team that will go for its third victory of the year over the rival Orange on Friday night now has many ways to get to its opponents. Porter is, of course, the focus. But as Starks said, “We’re all on the scouting report.”

With Porter hemmed in for much of the first 35 minutes — he hit just 3 of 9 field goal attempts — Starks did his part with 14 points on 6-of-10 shooting. Freshman D’Vauntes Smith-Rivera scored 13 and guard Jabril Trawick added nine, each with a pair of threes. The run that put the Hoyas back on top featured five baskets from four players.

“Otto’s getting a lot of attention, and he should,” Thompson said. “He’s an outstanding player, one of the — if not the — best player in the country, in my opinion. But we have a very good team.”

It is that team that will face Syracuse once again, just six days after the two ended their regular season Big East rivalry in a 61-39 blowout for Georgetown at Verizon Center. The Orange survived in the final minutes in Thursday’s 62-59 win over Pittsburgh. Fittingly, Georgetown awaits.

“We’re trying to pretty much return the favor,” Syracuse guard Brandon Triche said. “That means a lot. Any team that beats you by 20 points, you want revenge.”

The revenge will have to come against a Georgetown team that appears ready — ready to respond to lulls in its own play or spurts by an opponent, ready to turn elsewhere if Porter gets bottled up, and ready to make this final Big East tournament memorable.