As the lead swelled from eight to 15 and eventually more than 20, standing ovations grew in intensity.

The cheers, though, were not from the Duke contingent at the Garden enjoying another win by the third-ranked Blue Devils. It was from the St. John’s portion of the sellout crowd, who had every reason to let loose as it witnessed the Red Storm blow out the defending national champions 93-78.

“We know we’re not favored to win,” said Dwight Hardy after scoring a team-high 26 points. “It goes to show when we play St. John’s basketball, we can play with anybody in the country.”

St. John’s (12-8, 4-5) didn’t just outplay its opponent, it dominated Duke.

In what coach Mike Krzyzewski described as a “beautiful performance,” the Red Storm surged up and down the court for most of the afternoon on both ends and led for the final 35:50.

“We had this game circled as a game we wanted to win,” forward Sean Evans said.

It’s a game the NCAA?tournament committee might be circling come March. The win will pump up the Johnnies’ RPI of 28 and could go a long way in determining if they go dancing for the first time since 2002.

“It helps out a lot, confidence wise, and of course when they look at our résumé,” said forward Justin Burrell. “But ... it only counts as one win, so we have to go out and win more games in order to be able to play in the NCAA tournament.”

St. John’s desperately needs consistency to start accumulating those wins. It just completed a stretch of eight straight games against ranked opponents that featured home wins over Georgetown and Notre Dame as well as blowout losses to Syracuse and Louisville.

“Right now, St. John’s is a team that holds its hat on playing defense,” Burrell said. “Sometimes we don’t bring that effort into playing defense at a high level but when we do, you have wins like Notre Dame and Duke.”

And if it doesn’t, Steve Lavin’s crew could lose home games such as Wednesday’s matchup with Rutgers, which nearly knocked off Big East leader Pittsburgh on Saturday.