No. 9 St. John’s and No. 24 Creighton will battle for the Big East lead on Sunday afternoon at Madison Square Garden in New York.Both teams have been reminded this week of the thin line between euphoria and disappointment, as both will be looking to rebound from rare losses.The Red Storm last played Wednesday, when their 10-game winning streak ended with a 73-71 setback at Villanova. The Bluejays had won nine in a row before falling to visiting UConn 70-66 on Tuesday.The loss by Creighton (18-7, 11-3 Big East) ensured St. John’s (21-4, 12-2) would remain alone atop the conference, at least heading into the weekend. But the Bluejays’ visit to New York will serve to further emphasize the small margin of error for the Red Storm, whose four defeats have been by a combined seven points.One of those was a 57-56 loss at Creighton on Dec. 31, which means a win Sunday by the Bluejays would give them the tiebreaker for Big East tournament seeding purposes.An atypically mediocre defensive performance by St. John’s on Wednesday also provided a reminder of the challenges of trying to win with an old-fashioned approach. Per KenPom.com, the Red Storm entered Friday with the nation’s second-ranked defense but the 80th-ranked offense.The Red Storm exceeded their Big East averages by shooting 44.3 percent overall and 29.7 percent from 3-point land Wednesday night. But Villanova shot 53.1 percent from the floor and 45.8 percent from beyond the arc.”We weren’t there defensively, and that’s our identity,” St. John’s guard Aaron Scott said. “I don’t know (why). They have some good players on their team, but we just weren’t there defensively.”The Red Storm will need to solve their issues on both ends without guard Deivon Smith, who is out indefinitely with a neck injury.”He’s just not the same player he was a month ago and we’ve got to get him healthy,” coach Rick Pitino said of Smith, who also missed three games last month with a bruised right shoulder.