NEW YORK—After building a large lead against a struggling team, Marquette narrowly avoided a short stay at the Big East Tournament.Henry Ellenson had 27 points and 14 rebounds, Jajuan Johnson scored 23 points off the bench and Marquette held off a furious rally by feisty St. John’s for a 101-93 victory in the first round Wednesday night.Freshman guard Haanif Cheatham added 19 points for the seventh-seeded Golden Eagles (20-12). They advanced to play fifth-ranked and second-seeded Xavier in the quarterfinals Thursday night. ”We’re going to pull out the AAU handbook on two games in one day, and see how the best advance in the platinum division,” Marquette coach Steve Wojciechowski said. ”They know who Xavier is. Xavier is a team that is capable of winning a national championship.” Facing a last-place squad that managed only one conference victory all season, Marquette opened a 17-point bulge midway through the second half but then briefly fell behind in the final minutes. Ellenson and his teammates made just enough plays down the stretch to prevent an upset that would have all but ended their flickering hopes for an NCAA bid.Christian Jones scored a career-high 29 points for the 10th-seeded Red Storm (8-24). After overhauling the roster from last year’s NCAA Tournament team, they dropped 21 of their final 22 games in former star Chris Mullin’s first season as coach. ”Much like our whole season, I was proud of my guys’ effort. We had a tough first half. Regrouped, and just didn’t give up,” Mullin said. ”The results are frustrating. Don’t get me wrong, that’s a lot to deal with. But the future is bright. … We know we have a lot of work to do.” Hours after picking up his Big East freshman of the year trophy at Madison Square Garden, Ellenson shot 8 for 16 from the field and 9 of 10 at the foul line.Johnson hit all eight of his free throws, and Marquette was 38 for 43 (88.4 percent) at the line.