Brittany Hrynko scored 15 points and Megan Rogowski added 14 on Tuesday and No. 23 DePaul beat St. John's 65-57 to capture its first Big East women's tournament championship.
Megan Podkowa had 12 points and Jasmine Penny added 11 as the host Blue Demons (27-6) won their seventh straight and earned the league's automatic NCAA tournament berth.
Aliyyah Handford scored 13 points and Briana Brown added 12 for the Red Storm (22-10), making their first Big East title game appearance since 1988.
DePaul never trailed in the second half after taking a 30-29 lead just before halftime.
It was the first women's championship game for the realigned Big East since powerhouses Connecticut and Notre Dame departed last year for the American Athletic and Atlantic Coast conferences, respectively.
The championship tournament was also held for the first time in Chicago after Connecticut hosted the past 10 years.
DePaul also finished atop the regular season standings for the first time since joining in 2005-06.
DePaul took an early 15-9 lead, but Handford scored five points in a 9-2 run that gave the Red Storm their first edge at 18-17 on a layup with 8:52 remaining.
Hrynko answered with a 3-pointer for a 20-18 Blue Demons lead. Three players later combined on seven unanswered points to put St. John's up 25-22 with 4:11 remaining.
The lead changed hand twice more before DePaul took a 30-29 advantage into the half after Rogowski's layup with 37 seconds left.
DePaul led by seven points through the mid stages of the second half, including a 49-42 edge at the 9:57 mark on Rogowski's layup off an inbound pass.
The Red Storm closed the gap to four at 57-53 on Brown's 3-pointer with 2:24 left. Rogowski followed with two free throws and Penny banked in a shot with 1:54 left for a 60-53 lead.
Brown recovered a loose ball for a layup to cut the DePaul lead to 60-55 with 45 seconds to play, but Chanise Jenkins hit a pair of free throws two seconds later to restore a seven-point lead.
Connecticut captured seven Big East tournament titles from 2005-12, plus last year's NCAA championship. Notre Dame won the 2013 league tourney on the way to its third straight Final Four appearance.
Both remained unbeaten after winning conference titles this week and are ranked No. 1 and No. 2 nationally.
"They're off the charts," DePaul coach Doug Bruno said. "I never felt bad about what we achieved in the previous Big East. It was no disgrace to get to the semifinals in that league. If you could go to the final four of the old Big East, you could go to the Final Four of the NCAA tournament."
Whether the new Big East produces a Final Four entry won't be known until next month. But the current 10-team league -- eight from the previous league plus Butler and Creighton -- now features more balance and competitive play.
Regular-season champion DePaul was 15-3 in conference play while runner-up St. John's went 13-5.
In Monday's semifinals, St. John's had to rally in the second half to force the first overtime then a second before beating Creighton. DePaul held off a late Marquette comeback and didn't secure its win until hitting six free throws in the final minute.