It was Sunday — only in reverse.

Instead of a poor start, there was a fast one. Rather than rushed possessions, there was patience. When the opponent turned up the pressure, St. John’s performed its best.

So, three days after a disappointing 11-point loss at No. 20 Iowa State, coach Mike Anderson’s team showed its greatest strength so far this season: resolve.

The Red Storm answered their ugly loss on Sunday with their best performance of the year, a thorough 86-67 victory over DePaul at Carnesecca Arena to open the conference season in style.

“You think about the Iowa State game … I think it exposed some of the things we got to get better at,” Anderson said. “Sometimes when you get bumped upside the head you learn something.”

St. John’s (9-1, 1-0) got off to by far its best start of the season, taking a 12-0 lead 4:32 in. It scored on its first three offensive possessions and held the Blue Demons (5-4, 0-1) scoreless over the opening 5:15. The Red Storm never looked back, leading by 16 in the first half and by as many as 24 after halftime.

Prior to the opening tip, new St. John’s wing David Jones went over to greet one of his old teammates and was given the cold shoulder. It sparked the DePaul transfer.

“We’re about to play basketball right now, let’s see,” Jones recalled saying. “That’s what I was a little bit hyped about.”

His teammates were ready to go, too.

Joel Soriano took advantage of the absence of DePaul’s top two big men, Nick Ongenda and Yor Anei, with his eighth double-double of the season. He was dominant, producing a 17-point, 14-rebound, two-block performance that included a monster jam which brought the large crowd to its feet. One of the most improved players in the country, the 6-foot-11 Soriano rebounded from his off night against Iowa State.

“When you talk about what was the difference in the start, I think that was the difference. We started inside,” Anderson said. “We got some of their guys in foul trouble, and then it opened up the lanes where we could get in there and attack the basket.”

Posh Alexander was all over the floor — notching 13 points, six rebounds, six assists, three steals and a plus-25 rating in 34 minutes — and Andre Curbelo had 15 points and five assists. Jones added 11 points and eight rebounds against his former team. Zion Cruz led DePaul with 14 points.

It was a significant showing for a team still looking to find itself. Despite the gaudy 9-1 record, slow starts and inconsistency have held St. John’s back. Against DePaul, it put forth a more complete effort, holding the Blue Demons to 39 percent shooting, forcing 14 turnovers and winning the battle on the glass by 10.

“Defensively that’s probably the most consistently [we’ve played],” Anderson said. “We played the game the right way and the game rewarded us with the win.”

Graduate guard Montez Mathis (10 points) suffered a right ankle injury with 7:58 left in the second half and didn’t return.