DAYTON (AP) -- Don't get discouraged, coach Cuonzo Martin told his Volunteers during those long NCAA tournament timeouts. Instead, hang in there and figure a way to pull it out.
They went about it a most improbable way.
With forward Jarnell Stokes using his 280 pounds to dominate inside and a highly regarded defense finally locking in, Tennessee pulled off the first amazing comeback of the NCAA tournament.
Stokes opened overtime with a three-point play that put Tennessee ahead to stay, and the Volunteers' defense shut down Iowa in overtime for a 78-65 victory on Wednesday night, finishing off the First Four with an exclamation point.
"I told our guys we've been through everything this season, keep your composure down the stretch," said Martin, who got his first NCAA tournament win in his third season at Tennessee. "Find ways to win the ball game."
The Vols (22-12) head to Raleigh, N.C., where they'll play sixth-seeded Massachusetts on Friday in the Midwest Regional. They left Dayton with a lot of momentum -- six wins in their last seven games.
"We did a tremendous job toward the end of fighting back," said Jordan McRae, who had 20 points. "We did a great job on our defense. For us to hold them like we did was a great job."
Tennessee didn't lead until Antonio Barton's 3-pointer put the Vols up 59-57 with 3:05 left regulation. There were five lead changes before McRae missed a jumper missed at the buzzer, leaving it tied at 64.
No surprise that Barton made the big shot. The senior transfer is the only Volunteer with any significant NCAA tournament experience, having appeared in three of them with Memphis.
Stokes' three-point play in overtime was the key moment in his 18-point, 13-rebound performance, putting the Volunteers ahead to stay. It was his 20th double-double this season, the most by a Volunteer since Bernard King had 22 of them in 1976-77.
Tennessee's highly regarded defense took it from there, holding Iowa (21-13) to one free throw the rest of the way. The Hawkeyes missed all eight of their shots from the field in overtime.
"You go through anything so often -- being in those games, being in those situations -- we're a much better team the last eight games," Martin said. "Guys stepped up and made plays."
It was a tough ending to a long and stressful day for Iowa coach Fran McCaffery. He started the day in Iowa with his teenage son, Patrick, who had surgery to remove a thyroid tumor. His assistant coaches led the Hawkeyes through a meeting and their final practice, and McCaffery was back by game time.
Martin and the Volunteers hugged him after the game and wished him well.
"Their players hugged me and told me they were thinking of me," McCaffery said. "I was really impressed with their guys and the program Cuonzo has built there."
Adam Woodbury had 16 points for Iowa, which got a subpar performance from its leading scorer. Roy Devyn Marble was only 3 of 15 from the field for seven points, matching his season low.
"I don't think we ran out of gas," Woodbury said. "We made some key mistakes down the stretch and that hurt us."
The ending will sting the Hawkeyes for a long time. They were struggling as they headed into their first NCAA tournament appearance since 2006, losing six of their previous seven games. Defense was the biggest problem, often letting them down in the second half.
They opened the game in promising fashion, switching from man-to-man to zone to half-court traps. It worked. They got off to a 16-4 lead and were still ahead 29-26 at halftime.
They kept swatting away the Volunteers' runs until the last few minutes of regulation.
Marble's basket tied it at 64, and he was guarding McCrae when he missed his fade-away shot at the buzzer sending it to overtime.
Tennessee got an at-large bid by closing the season with a defensive flourish. The Volunteers won five straight before losing to No. 1 Florida 56-49 in the Southeastern Conference tournament. They gave up 61.1 points per game, second only to Florida in the SEC, and allowed an average of only 47.4 points in the last four games.
In overtime, that defense decided it.
NCAA FIRST FOUR
CAL POLY 81, TEXAS SOUTHERN 69
DAYTON -- Chris Eversley scored 19 points and Cal Poly avoided its 20th loss of the season and won its first NCAA tournament game with an 81-69 victory over Texas Southern in the First Four.
The Mustangs (14-19) were 0-3 and 4-9 early before losing nine of 11 heading into the Big West Conference tournament -- which they won to earn the program's first NCAA bid.
The team with the worst record in the tournament now moves on to face the one with the best -- top-seeded Wichita State (34-0) -- in the second round in St. Louis on Friday.
Aaric Murray, the former La Salle and West Virginia player, closed out his career with 38 points for Texas Southern (19-15), champs of the Southwestern Athletic Conference tournament.