(Photo credit: Bill Streicher-Imagn Images)

PHILADELPHIA -- Tennessee may be known for its defense, but a balanced and efficient offense has led the Volunteers to their fourth straight Sweet 16.

Ja'Kobi Gillespie put up 21 points and six assists, Bishop Boswell had 13 points and nine assists and the sixth-seeded Volunteers took down third-seeded Virginia 79-72 on Sunday in a second-round NCAA Tournament matchup.

Tennessee (24-11), which will meet No. 2 seed Iowa State in the Midwest Region semifinals, also got 16 points from freshman Nate Ament after he played 18 scoreless minutes in the first round while working through an ankle sprain. Ament scored 13 in the second half, overcoming a few critical mistakes.

J.P. Estrella and Jaylen Carey scored 10 apiece for the Volunteers, who had 20 assists on 26 made baskets.

Belgian freshman Thijs De Ridder powered Virginia's comeback with 17 of his 22 points in the second half. Malik Thomas added 12 and Jacari White and Chance Mallory had 10 apiece.

The Cavaliers (30-6) shot a meager 34.4% in the first half, missing eight of 11 layups, but turned it around in time for a second-half charge.

Tennessee led 36-31 at halftime and expanded it to as many as nine points. Gillespie heaved a long 3-pointer to beat the shot-clock buzzer, and after De Ridder responded with a quick layup, Estrella's fastbreak dunk made it 62-53 with 9:15 to go.

But the Cavaliers were in the midst of a 7-for-7 shooting run, with Johann Grunloh's dunk past Ament cutting the deficit to two. De Ridder tied it twice for Virginia, the second time at 68-68 on a layup after Ament tried to run the baseline when he couldn't and turned it over.

Virginia capitalized on another mistake when Ament couldn't corral Gillespie's inbounds pass and it sailed to the bench. De Ridder's ensuing 3 gave the Cavaliers their first lead of the half, 71-70, at 2:03.

But that was the last field goal Tennessee would allow. Ament put the Vols ahead for good from the line, as Tennessee scored its last nine points on free throws.

In the early going, White tied the game at 14 and then broke that tie on consecutive 3-pointers. Virginia led by four when Tennessee launched a 12-0 run with a pair of layups by Jaylen Carey.

Gillespie and Boswell knocked down treys and DeWayne Brown II set up Felix Okpara for an alley-oop dunk to make it 28-20 with 6:34 left in the half.

Okpara contributed seven points, eight rebounds and four blocks while playing stellar defense for Tennessee.

--Adam Zielonka, Field Level Media