Late in the first half of Maryland men’s basketball’s season opener against Delaware, Blue Hens forward Eric Carter set a screen to try to free up space for guard Kevin Anderson.

With the shot clock ticking beneath five seconds, Terps forward Bruno Fernando simply switched off Carter and closed down on Anderson, blocking his three-point attempt. Guard Eric Ayala was quickly fouled on the other end and sank both free throws, pushing Maryland’s lead to double-digits for the first time Tuesday night.

That sequence was part of the 15-1 run sparked by Maryland’s defense at the end of the first half, finally giving the team some breathing room in its first game of the year.

But the Terps’ defense faltered after halftime. Fernando’s foul trouble allowed Carter to feast on the inside, and coach Mark Turgeon said his team allowed its offensive struggles to affect its play on the other end. That gives the young group something to learn from entering its game at Navy on Friday.

“We stopped guarding. We didn’t play very smart,” Turgeon said. “We can’t let it carry over.”

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The Blue Hens scored 27 points in the first half and went 2-for-10 from beyond the arc, allowing Maryland to carry a 17-point lead into intermission despite a stop-and-start offense.

The Terps opened up a 22-point advantage early in the second half before Fernando earned his third foul, forcing him to play just two of the next seven minutes. Delaware went on a 17-4 run during that time, and Carter scored 12 of his 29 points.

“The difference was, Bruno picked up his third foul,” Turgeon said. “We couldn’t guard [Carter] after that. He [only] scored a couple of times on Bruno.”

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Maryland also began losing track of the Blue Hens’ shooters late. Delaware opened the game 2-for-16 on 3-pointers, but made four of its final seven shots from beyond the arc.

The Terps’ defensive letdown was reminiscent of last year’s team, which ranked 13th in three-point defense during Big Ten play.

“We just got a little down defensively,” Fernando said.

But Turgeon and his staff believe there was more to it than that. The Terps struggled shooting all night, going 2-for-19 from beyond the arc. Turgeon said it was “one of those nights when we just started missing,” which played a role in the defensive lapses.

“Even though we couldn’t make a shot,” Turgeon said, “the game should’ve never gotten that close.”

Maryland went scoreless for a five-minute period midway through the second half, with Fernando on the bench for most of that.

But cold shooting nights and fouls are unavoidable over the course of the season, so Turgeon took the opportunity to emphasize to his team following the narrow victory the importance of remaining mentally sound.

“They pretty much wanted us to take away how our second half turned,” forward Jalen Smith said. “Our offense affected our defense. We can’t allow that to happen … and let teams back in the game.”