NEW YORK -- Duke coach Mike Krzyzewski was worried about a letdown after three tough conference wins. He didn't need to be.
"We are obviously pleased about the win," Krzyzewski said. "We had played three really emotional games in our conference when we were 5-6 (in the Atlantic Coast Conference) and won all three, two of them away. With the young team we have, I was worried about letting up. We didn't. We were very prepared to play."
Jon Scheyer had 11 points, and David McClure grabbed seven rebounds to help Duke (22-7, 8-6 ACC) win its fourth straight since a four-game losing streak knocked the Blue Devils out of the AP poll. Duke's first three wins during the streak were by a combined 22 points, including 71-66 at Clemson on Thursday night.
Josh McRoberts added nine points, six rebounds and six blocks for the Blue Devils, and Paulus shot 6-for-10 from the field, including 5-for-7 on 3-pointers.
"Greg played great," Krzyzewski said. "His five 3s were huge. And Josh's ballhandling and ability to handle things, those two guys and DeMarcus -- our three veterans -- were the key guys today."
Lamont Hamilton scored 17 points and Anthony Mason Jr. had 13 to lead St. John's (15-14, 6-9 Big East). The Red Storm shot 34 percent from the field, hitting 3 of 22 shots in the first half. St. John's trailed 34-10 at the break with their lowest-scoring opening period of the season.
"Give Duke a lot of credit," Red Storm coach Norm Roberts said. "They have a terrific team. We got ourselves down too much in the first half."
Duke improved to 14-1 against nonconference foes this season, and beat St. John's for the fourth straight time. The Blue Devils also won their second game at Madison Square Garden this season, including a victory over Gonzaga on Dec. 21.
Nelson hit two free throws with 16:14 left to give Duke a 41-16 lead. After Hamilton's 3 with 15:51 remaining, Paulus responded with one 25 seconds later to restore the 25-point advantage.
St. John's then began chipping away, using a 10-2 run to pull to 46-29 on Mason's putback with 9:35 to go.
"What we talked about at halftime was playing with more pride and more urgency and getting through those screens," Roberts said. "We did compete much harder in the second half. We just can't get ourselves down that much that early."
Paulus hit his fifth 3 just 24 seconds later to push the lead back to 20.
The Red Storm had an 8-0 run, the last four points on free throws by Mason, to pull to 51-39 with 4:15 left.
"We played brilliantly in the first half where we won the game and we weren't in danger," Krzyzewski said. "But I would have liked to have played better in the second half, obviously."
McClure made a layup with 2:41 to go to push Duke's lead to 55-41. Scheyer hit a pair of technical free throws 29 seconds later when St. John's was issued a delay of game because two T-shirts were thrown on the court by fans during a timeout.
"I don't think they should throw stuff on the court but they stayed behind us and tried to get us back in the game," Hamilton said.
Scheyer added a layup to push the Blue Devils' lead to 18 with 1:27 remaining.
There were two sets of double technicals. The first came with 16:34 left in the game when there was pushing and shoving under the basket, and Duke's Josh McRoberts and St. John's Aaron Spears were whistled for the violations. A second was called on Nelson and Eugene Lawrence with 11:43 to go. The Red Storm's Qa'rraan Calhoun also received one early in the second half.
Duke scored the first 12 points of the game, taking the lead on McRoberts' free throw 31 seconds in. St. John's didn't get on the board until Mason's jumper with 14:55 left in the opening period.
"It's a good situation to be in where you have a big lead, which is what haven't had in most of our games," Krzyzewski said. "It's uncharted waters for us, and we don't know how to navigate. When you get a big lead like that early, there is a lot of game left."