Anna Martin scored 17 points to lead No. 12 DePaul to a 66-54 win over St. John's on Sunday in the quarterfinals of the Big East tournament.
Keisha Hampton and Katherine Harry each added 10 points for the Blue Demons (27-5), and Sam Quigley had nine points and seven assists.
Nadirah McKenith had 12 points and seven steals, Amanda Burakoski had 11 points and Da'Shena Stevens added 10 for St. John's (21-10).
The second-seeded Blue Demons led by nine at the half, and St. John's could not get closer than seven points the rest of the way.
The seeding is the Blue Demons' highest since they joined the league in 2005-06.
DePaul is now 6-5 in Big East tournament play, with all six wins coming in the team's opening game.
DePaul will play in Monday's semifinals against Notre Dame, which beat Louisville 63-53 later Saturday.
Much of DePaul's offense early consisted of throwing the ball to Felicia Chester in the middle, who would kick it out to one of the perimeter players for a 3-point attempt.
The Blue Demons made just three of their first nine from behind the arc, but shot 50 percent from the floor and led 19-8 midway through the first half.
St. John's hit just four of its first 16 shots, none of them from 3-point range.
A 13-2 run gave DePaul a 25-10 lead with 8 minutes left in the half. But the Blue Demons had just four more points, before China Threatt hit a 3-pointer with 2 seconds left to give DePaul a 32-23 lead at the half.
DePaul led by as many as 14 in the second half. A steal and layup by Nadirah McKenith cut the lead to 59-52 with 2 minutes left, and another McKenith layup off a turnover made it 61-54 with 1 minute remaining.
But St. John's was forced to foul and the Blue Demons extended the lead from the line.
St. John's shot just 32 percent from the floor, while DePaul hit 45 percent of its shots.
The Blue Demons, who had 215 3-pointers in the regular season, made just five of 18 shots from behind the arc. But when the Red Storm would come out to guard them, DePaul's guards were able to penetrate and either dish off or score.
DePaul also won the regular-season meeting between the teams, beating St. John's 69-54 in New York in January.
St. John's had won seven of its last 10 games.
Since the start of the 2003-04 season, DePaul is 143-25 when holding opponents to less than 70 points.
This was the first-ever meeting between the two schools in the conference tournament.
St. John's is 3-8 all-time in Big East tournament play under coach Kim Barnes Arico and has never made it past the quarterfinals.
DePaul has won five of its last eight games, including a 70-69 win over Notre Dame on Feb. 28 to earn the tournament's No. 2 seed.