When Patrick Ewing and Greg McDermott stood in front of Georgetown’s bench for a pregame chat Monday night, the Hoyas’ second-year coach and Creighton’s ninth-year coach — who was readying for his 300th game with the Bluejays — bonded over a common plague.

They spoke about the close games both programs had let slip through their fingers. For McDermott, there had been a particularly bruising overtime loss against then-No. 21 Marquette this month. For Ewing, the list was longer: three tight losses in Big East play in the past 16 days.

Next time, Ewing will have even more to talk about. Georgetown added to its litany of painful defeats at Capital One Arena with a 91-87 loss to Creighton. McDermott said afterward that young teams such as Ewing’s take a while to figure out how to win close games. But Ewing, with resignation in his voice, was more blunt.

“We’ve just got to make plays. We have to make plays. We can’t make any excuses,” he said. “We have to be able to guard our men individually, but then when we get beat, know that we have help. Tonight, we didn’t do a good enough job of guarding our individual men, and then when we helped, they knocked down threes.”

Georgetown’s defense couldn’t stop one of the top offenses in the Big East, and the Hoyas’ scorers couldn’t measure up, either.

Creighton made 13 of 29 three-pointers and shot 47.6 percent from the field. The Bluejays scored 18 of their points on fast breaks and, in an achingly close game — both on the court and statistically — they were just a play or two better.

Ty-Shon Alexander hit a three-pointer with 55 seconds left that sucked the energy from the crowd, deflated the Hoyas (12-7, 2-4 Big East) and gave Creighton (11-8, 2-4) the lead for good.

“I thought that we had our opportunities to win the game,” said Ewing, Georgetown’s lone representative after the game because players were not made available to the media. “I thought that Jessie [Govan] got fouled at the one shot he took, [but] no call was made. Then we went into scramble mode, and we can’t let — Alexander, he had a wide-open three. He was killing us all night, and I can’t remember what happened on the play, but I knew he was wide open for a three.”

The Hoyas shot 12 for 27 from three-point range and shot 49.2 percent from the field. But defense ultimately made the difference in a game in which Creighton had five scorers in double figures.

Alexander led all players with 26 points, including six three-pointers, and Davion Mintz, the floor general in the Bluejays’ four-guard, shooter-heavy lineup, had 17 points.

Govan led the Hoyas with 22 points and 12 rebounds, and Mac McClung and Josh LeBlanc had 10 points apiece.

After — what else? — a close first half, Creighton took its first lead on a three-pointer from Mitch Ballock just after halftime as part of a 14-5 burst to grab a 53-47 advantage and force Ewing into a timeout three minutes into the second half.

The Hoyas stayed close after that, and their chance to tie finally came after they got a stop on defense with a block from Jamorko Pickett. Georgetown was able to string together back-to-back three-pointers from Govan and Jahvon Blair to tie the score at 70 with just under nine minutes left.

Eight minutes of trading baskets ensued until Alexander’s three with under a minute to play.

Ewing said he takes no solace in knowing his young team is just a possession or two away from closing out some of these tight games.

“At the end of the day, it’s a loss,” Ewing said. “We have to grow up fast. The freshmen have to grow up faster than they’re growing up. The upperclassmen have to step up and get the job done.”

The Hoyas opened the night with a few changes to the starting lineup. Ewing replaced Pickett with Greg Malinowski and James Akinjo with Jagan Mosely. Akinjo had started all 18 games of his Georgetown career, but the freshman point guard had disregarded Ewing’s play-calls in critical, late-game moments in both of Georgetown’s previous two games.

Akinjo had an off shooting night Monday, going 2 for 11 from the field for six points after checking in with just under 13 minutes left in the first half, but he dished 11 assists — the most for a Hoyas player in a game since 2014. Ewing said he was pleased with Akinjo’s playmaking.

After a missed opportunity against a Creighton team that entered on a four-game losing streak, the road ahead for the Hoyas is a challenging one. They play three of their next four games at St. John’s, No. 18 Villanova and Providence. Their lone home game in the stretch is against Xavier on Jan. 31.

Ewing knows Georgetown is running out of time in Big East play to sort out its defense. He was asked Monday whether he was surprised by how long it has taken for Georgetown’s defense to come together, considering it was his bread and butter throughout his playing career.

“Sometimes you have your defensive schemes, but you also need defensive players to carry them out,” he said. “And we’ve got some great offensive players. We have some guys that can play defense, and I just have to find the right blend.”