Pavin Smith homered and drove in three runs and Brandon Waddell turned in another strong College World Series pitching performance, leading Virginia over Vanderbilt 4-2 on Wednesday night for the school's first baseball national championship.

The Cavaliers (44-24) prevailed in the CWS finals rematch against the defending champion Commodores and won the Atlantic Coast Conference's first title in baseball since Wake Forest in 1955.

Waddell (5-5) went seven innings and allowed only two hits after Vanderbilt (51-21) scored twice in the first. He retired the last 11 batters he faced. It was Waddell's fifth career CWS start, and Virginia won each of them.

Nathan Kirby pitched the last two innings and struck out five of his eight batters for his first save. John Kilichowski (3-4) took the loss.

When pinch-hitter Kyle Smith got caught looking at a fastball to end the game, Kirby threw his glove and hat into the air as catcher Matt Thaiss ran to the mound to embrace him.

Virginia's 44 wins were the fewest by a national champion since the 1968 Southern California squad had 43. The Cavaliers endured a season of injuries and tough times at midseason and almost missed qualifying for the ACC Tournament. They entered the NCAA Tournament as a No. 3 regional seed.

The Commodores had a second straight season with more than 50 wins, and they came into Wednesday having outscored their first nine NCAA Tournament opponents 70-15. They couldn't generate much after scoring their two runs in the first.

Smith stepped up for Virginia in Game 3 after going 1 for 8 and striking out four times in the first two games of the finals. He hit a two-run homer off Walker Buehler to tie it in the fourth, singled in the go-ahead run in the fifth and flashed defensively all night at first base.

Waddell was pitching on three days' rest after working the first five innings of the Cavaliers' 5-4 win over Florida on Saturday. Before that, he and Josh Sborz combined on a two-hit, 1-0 shutout of the Gators on June 16.

Sborz, who won three games and pitched 13 scoreless innings, was selected as the CWS Most Outstanding Player.

Kirby, who missed nine weeks because of injury and returned to start Virginia's 10-5 loss to Florida in its third CWS game, relieved Waddell to start the eighth and struck out the side. With a man on first, he fanned No. 1 overall draft pick Dansby Swanson for the second out.

Swanson, the 2014 CWS Most Outstanding Player, stood with his hands on his hips and shouted "No!" as first-base umpire Perry Costello ruled he didn't check his swing on the third strike, ending his final collegiate at-bat.

The Cavaliers also got another big game from Kenny Towns. He saved what would have been the go-ahead run for Vanderbilt in the fourth when he made a diving stop of a smash down the third-base line and threw out Tyler Campbell to end the inning. He later drove in an insurance run in the seventh.

Buehler, the 24th overall draft pick by the Los Angeles Dodgers, lasted only three innings in what was the second-shortest of his 15 starts this season. He allowed three hits and walked a season-high four.