Conner Delaney could have stuck with his original college decision back when he was at Episcopal Academy: Play lacrosse at Villanova.

“I just really couldn’t see myself not as a basketball player,’’ Delaney said about why he changed his plans, decommitting from Villanova to play Division III basketball at Johns Hopkins instead of Division I lacrosse up the road.

If you were at Swarthmore College on Saturday, you saw why Delaney made that decision, and its impact.

A 6-foot junior point guard, ball in his hands, Centennial Conference title game, clock winding down, the last undefeated NCAA men’s basketball team in America defending. Delaney already had put 30 points on Swarthmore, but that gave Hopkins only a tie. One more play, for the win.

“Conner,’’ yelled his coach, Josh Loeffler.

“I didn’t want to complicate things,’’ Delaney said. “I waved him off.”

Delaney thought his coach wanted a timeout.

“I didn’t want to call a timeout,’’ Loeffler said, explaining that he wanted Delaney just to take his time, to make sure the shot really was the last shot, since the season before, a Hopkins shot with a few seconds left had turned into a miracle win for an opponent. “All you really want to do is get the last shot, and hopefully it’s going to your best player, and he already has the ball.”

“Didn’t want Swarthmore to set something up,’’ Delaney said later. “Worse-case scenario, going to overtime.”

There was no overtime.

Hopkins was smart enough not to try to set a ball screen for Delaney, since that would have brought a second Swarthmore defender into the fray.

When the clock hit 5 seconds, Delaney hit the go button and took it to just right of the foul line, four dribbles, including a crossover, then a pullup to his left, just enough instantaneous space to get a clear shot on a 15- or 16-footer, ball leaving his fingertips with a second left, ball filling up the net, Delaney punching the air before being engulfed by teammates.

Make that 32 points.

The game had been of the highest quality, 73-71 final score, as good as the sport provides. The largest Hopkins lead had been five points, the largest Swarthmore lead was four points, so every possession was played within the parameters of that tight margin. There was never a time when you could even guess who might win it in the end. The defense was legitimate and tight, yet each team had just seven turnovers. Swarthmore made 50% of its shots and Hopkins was one make under 50%.

Both teams move into NCAA Tournament play, each opening at home Friday. They can’t face each other for a fourth time unless they reach the NCAA final. For now, they’ve played 27 games each and only lost one that wasn’t to the other. Hopkins (24-3) will face Penn State Harrisburg (20-7) in Baltimore in one regional first-round game; Swarthmore (26-1) will host Brooklyn College (13-15) in another.

This week, Delaney, who grew up in Garnet Valley, was named Centennial player of the year. So that original decision looks pretty sharp, especially for a math major in the Hopkins engineering school.

“The kid has taken courses that I didn’t even recognize as math,’’ his coach said.

Delaney had been Inter-Ac League lacrosse player of the year as a senior, so just before he got to Hopkins, the coach at the D-I powerhouse wondered if he might want to play both sports. “Basketball was what I came here to do,’’ Delaney said.

“He’s a hooper,’’ Loeffler said.

Delaney had missed the second half of last season with a broken foot, making all this all the sweeter.

“It was tough to sit there and watch,’’ Delaney said.

Not this time. Delaney was the only player for either team to go all 40 minutes. Did he have enough left in the tank to make late plays?

“He’s very, very committed to being in the best possible shape,’’ said Loeffler, a former Fran O’Hanlon assistant at Lafayette, and a Swarthmore graduate himself whose younger brother Shane happens to be on Swarthmore’s staff. “He obviously possesses innate abilities that are hard to teach. He has a great sense of angles, time, space. And he can go by people.”

His shooting kept getting better.

“He puts more time in than almost anybody on his shooting,’’ Loeffler said. “He didn’t come with a pure stroke. He’s a self-made shooter.”

Afterward, Swarthmore coach Landry Kosmalski did what coaches do: beat himself up a little bit for not adding defensive wrinkles on the last play. The team practiced that scenario the very next day in practice.

“You just keep adding situations to your book,’’ Kosmalski said this week. “We’ve got to have something for this, and for that.”

This time, that was a guy comfortable in the moment, which was the biggest of his career, back in his home county, against the top-ranked Division III team in the nation.

Sorry, lacrosse, this guy knew right where he wanted to be.