Arizona State baseball did its best to put away Washington State early in a series-deciding finale Saturday night against light-hitting Washington State.

But nothing comes easy for No. 18 ASU, which squandered a 4-0 lead at Phoenix Municipal Stadium and needed an 11th-inning walk-off hit by Andrew Snow to win 6-5 and take its 10th series out of 13.

“I was about halfway down to first, and I was thinking he’s not going to get there and it dropped in,” Snow said of his game winner. “Then I see Trever (Allen), and it was awesome.”

ASU coach Tracy Smith compared the outgoing Snow to a Sesame Street character. “He’s all over. If you get on him, it doesn’t affect him. He’s got that energy and he’s naïve enough to go out there and want to be the guy that has the game on the line. I think everybody in the dugout felt that’s the guy we want at the plate, and that’s pretty unusual talking about a freshman.”

The Cougars pulled even in the seventh with two runs off closer Ryan Burr on a two-out double by Ben Roberts. Burr walked No. 9 batter Jack Strunc to start the inning, then first baseman Chris Beall failed to correctly cover first on a sacrifice, putting the eventual tying run on base.

Snow also made a leaping snag of a Shane Matheny line drive to end the seventh and prevent the Cougars from taking a lead. “I took a couple of steps to the left and jumped for it,” he said. “I snowconed it. That was a big play I guess. It got us going a little bit in the dugout.”

Washington State also turned in the seventh to its closer, Ian Hamilton, coming off a one-inning save Friday. He stranded two Sun Devils in the seventh, eighth and ninth. Burr, a junior making his 90th career appearance, held the Cougars in check in the eighth and ninth, sending ASU into extra innings for the third time in eight days.

The Sun Devils should have ended things quickly in the 10th after loading the bases with no outs, helped by Hamilton’s throwing error on a sacrifice. But third-base coach Ben Greenspan held Snow on David Greer’s fly to short right then Brian Serven and Colby Woodmansee struck out.

Cougars second baseman Shea Donlin, who pinch hit in the top of the inning, put Trever Allen on base with a fielding error to stop the ASU 11th. Jordan Aboites sacrificed Snow to second then Hamilton (0-4) intentionally walked Joey Bielek before freshman Snow’s second game-winning hit, a single to right.

Burr (8-2) pitched four innings, his longest career relief appearance, for the victory.

On Senior Day, the Sun Devils scored four first-inning runs, two of those on a home run to center field by fifth-year senior Allen.

Allen’s third homer following a two-run double by Serven put Washington State, which scored just one run in the first two games and came in hitting .241, into a substantial hole.

For Allen, his 20th career homer moved him into an exclusive club of now 17 Sun Devils with at least 200 hits, 100 RBI and 20 home runs. Others include College Baseball Hall of Famers Bob Horner, Oddibe McDowell, Alan Bannister and Mike Kelly.

Allen said of his final home Pac-12 game, “I can’t really explain it honestly. I’ve been here for so long, it was very emotional in the beginning of the game. It was an awesome win. I had so much fun with the guys.”

Seth Martinez, pitching in the No. 3 weekend starting slot for the first time this season after being at No. 1 since March 6, appeared to learn a thing or two watching Ryan Kellogg and Brett Lilek strike out 11 Cougars apiece Thursday and Friday.

The sophomore right-hander fanned the side in the first and finished with six strikeouts in five innings. But Martinez also gave a two-run homer in the fifth to Ian Sagdal, who struck out four times Friday, and left with a 5-3 lead.

Darin Gillies, who threw three innings Friday and gave up the only run of the game in the 10th inning, worked the sixth before ASU turned Burr, hoping for a three-inning save in his first appearance of the series.

ASU (32-19, 17-10 Pac-12) is in a virtual second-place tie in the conference with No. 16 USC (35-16, 16-9), which has Pac-12 games remaining against California on Sunday and Monday before hosting the Sun Devils in a series starting Friday. No. 23 Oregon State and Cal also are in the hunt for second behind No. 4 UCLA, which can clinch at least a tie for first Sunday with a win at Arizona.

Other seniors honored in addition to Allen were Gillies, Jake Peevyhouse and Bielek.

ASU will play one final regular-season home game at 6:30 p.m. Tuesday against Abilene Christian, the same opponent last year when it closed out its 40-year run at Packard Stadium.