St. Joseph's coach Phil Martelli is pumped up during the Hawks' victory over Georgia Tech. (AP)

Marvin O'Connor scored 13 of his 21 points in the second half when the Hawks blew most of an 18-point lead before recovering to beat Tech 66-62 on Thursday.

"We heard a lot of ACC (Atlantic Coast Conference). We took that personally," O'Connor said. "I guess they think the Atlantic 10 doesn't exist. I think they overlooked us. They probably don't know where St. Joe's is located."

Tech forward Jon Babul said, "It wasn't really a big deal."

St. Joe's, the second-smallest school in the 65-team tournament with 3,450 students on its Jesuit campus, saw its lead dwindle to three points twice in the final 1:43.

But the Yellow Jackets (17-13) came up short on two easy scoring chances. Tony Akins saw his shot spin out of the basket and Alvin Jones, the first Tech center to be chosen all-ACC, missed an alley-oop dunk.

The Hawks (26-6) missed the front end of free-throw attempts by Damian Reid and Jameer Nelson before Nelson hit two foul shots to keep St. Joe's ahead 65-60 with 29.7 seconds left.

"I think the guys were squeezing the ball to see if there was air in it," Hawks coach Phil Martelli said. "We started to play not to lose instead of playing to win."

Nelson added 13 points for St. Joe's, which led by 16 points in the first half. The Hawks tied the school record for victories in a season.

Akins led Tech with 16 points, including 7-of-7 free throws, and Darryl LaBarrie added 15 points. Jones finished with eight points and 10 rebounds after being held scoreless in the first half.

"I wasn't tired or frustrated, but I was a touch slow myself," Jones said. "Even before I started the game, I wasn't mentally focused, not like I was in the ACC Tournament."

Both teams were plagued by sloppiness in a game that saw Tech commit 17 turnovers to St. Joe's 14 and neither team shot better than 40 percent.

"I wasn't real pleased with our effort in the first half, but we came back well in the second half," first-year Tech coach Paul Hewitt said. "That gave us a chance. We just couldn't get a shot to fall."

St. Joe's, the ninth seed, is back in the NCAAs for the first time since reaching the Sweet 16 in 1997.

"For us to win and shoot 29 percent in the second half is very significant," Martelli said. "That was about a group of kids who didn't want their jerseys taken away."

Tech made the tournament for the first time since its Sweet 16 appearance in 1996. The Yellow Jackets, whose eighth seed equals their lowest ever, tied for fifth in the ACC, then upset Virginia in the conference tourney before losing to North Carolina in the semifinals.

A 3-pointer by O'Connor gave St. Joe's its largest lead, 46-28, early in the second half before the Yellow Jackets awoke.

Tech scored 15 of the next 17 points to get to 48-43 with 11:47 remaining. Jones had his first field goal of the game in the spurt and scored six consecutive points.

Halston Lane missed a dunk, but Tech controlled the rebound and Robert Brooks scored in the lane as the Yellow Jackets trailed 50-47.

O'Connor hit consecutive 3-pointers and scored on a dunk to push St. Joe's lead to 58-49 with 8:18 remaining.

Tied at eight, St. Joe's used an 18-2 run to take a 26-10 lead with 5:43 remaining. The Yellow Jackets went just under seven minutes without a field goal in that stretch. Bill Phillips had six points for the Hawks, including a backdoor basket that ended the run.

Georgia Tech got within eight on consecutive 3-pointers by Akins and Marvin Lewis, but Tech was outscored 13-4 over the final 3:38 to trail 41-24 at the break.