Before he entered his team’s locker room after Monday night’s game against No. 19 South River, Spalding girls’ basketball Coach Bookie Rosemond wondered aloud to his assistants: How could this happen? How could they let a 16-0 run in the fourth quarter slide?

Even though the sixth-ranked Cavaliers won, high expectations had been cemented weeks earlier and the postgame atmosphere was its most somber of the season. Spalding struggled in the second half and needed help to escape a 55-49 victory in Edgewater against the resilient Seahawks.

“After a win you’re supposed to be all cheerful . . . we came in here, heads down,” Spalding forward Camille Calhoun said. “We took it really bad . . . you’re supposed to win 70-30. It’s our goal to win every game 70-30.”

It looked as if Spalding (18-1) were going to play up to its own expectations Monday. It dominated the first three quarters inside and out, even with Calhoun sitting out the third quarter with foul trouble. When guard Torri Chesnut (14 points) hit a put-back layup to make it 53-31 with four minutes remaining, little did she or her team know it would be their last field goal of the night.

“Their confidence soared, and our confidence dipped,” Rosemond said.

The Seahawks (12-3) got plenty of help during a frantic 18-2 run in the final minutes. They used a slew of turnovers and missed free throws to rally. South River hit five-three pointers in that stretch, including three from standout guard Bre Bolden, who finished with 17 points.

“Our defense just stunk,” Calhoun said.

But after South River had cut it to 53-49 with just less than a minute remaining, Spalding found a way to survive.

Calhoun (nine points) came up with a critical offensive rebound off a free throw miss with 15 seconds to preserve the win.