SEATTLE -- Getting runners on base was not a problem for the Cleveland Indians on Sunday, no matter how long the series finale against the Seattle Mariners went.

Driving in those runs was a different story.

It took a bases-loaded walk, not one of Cleveland's season-high 18 hits, to drive in the go-ahead run before the Indians finished off their comeback with a 6-3 win over the Mariners.

"It was kind of a battle of wills," said Indians second baseman Jason Kipnis, who had two doubles, an RBI and scored a run to finish off an incredible offensive month in the win. " ... We stayed on them, kept pressure on them, and finally got it done at the end."

Cleveland (24-26) rallied from an early 3-0 deficit, finally getting over the hump when Seattle reliever Dominic Leone -- the Mariners' eighth pitcher used in the loss -- issued the bases-loaded walk to leftfielder Michael Brantley in the top of the 12th. Indians outfielder David Murphy, who had come on to pinch hit in the seventh inning, then drilled a two-run single to right field to give the Indians a 6-3 lead.

"A lot happened in that game," Mariners manager Lloyd McClendon said of a marathon that lasted more than 4 1/2 hours, the longest game for either team this season. "We had the early lead, and we couldn't hold it. ... Leone struggled with his command out there. That was pretty tough."

Indians reliever Zach McAllister (1-2) earned his first win of the season after pitching a scoreless 11th, while Austin Adams earned his first career save as Cleveland's seventh, and final, pitcher used in the game.

The Indians won despite leaving 17 runners on base.

"There was a lot of frustration during the game, but we kept at it," Cleveland manager Terry Francona said.

The Indians won for the first time this season after trailing through seven innings. They were 0-21 heading into Sunday.

The 4-hour, 36-minute game also included a Cleveland protest in the top of the 12th, as Francona believed that the final out was actually a foul ball.

Seattle (24-26) was outhit 18-5 in the game but never trailed until the top of the 12th inning.

Kipnis closed out an historic month with a pair of doubles and a sacrifice fly that tied the score 3-3 in the eighth inning. Kipnis had 51 total hits the month, the most ever by an Indians player in May, and his 15 doubles were the franchise's highest total since 1942. He scored his 30th run of the month in the top of the 12th.

"It was a fun month, not only for me but for the team," said Kipnis, who led all American League players with a .429 batting average in May. "It wouldn't have been nearly as fun if we weren't winning games."

The Mariners took a 3-0 lead on RBIs from first baseman Logan Morrison and center fielder Austin Jackson as well as a Dustin Ackley bunt that brought home a run on Cleveland third baseman Mike Aviles's throwing error in the fifth inning.

A diving catch by Cleveland right fielder Ryan Raburn prevented the messy fifth inning from getting any worse, ending a frame that included three hits, a walk, a wild pitch, a balk and the throwing error.

Raburn then led off the sixth with a home run, closing the Mariners' lead to 3-1. That sparked a two-run inning that included four hits as the Indians pulled within a run and chased Seattle starter J.A. Happ. The Mariners' Morrison got Seattle out of the jam when he turned a sharp grounder to first base into a double play from first to home plate.

Seattle's Happ allowed two earned runs off eight hits over five-plus innings.

Cleveland starter Danny Salazar allowed three earned runs off four hits and four walks over 5 1/3 innings. The Mariners did almost all their damage against Salazar in the fifth, as he retired the first eight Seattle batters of the game and didn't give up a hit until two outs into the fourth.

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