Hisashi Iwakuma pitched eight scoreless innings in Seattle's 6-0 win against Kansas City on Wednesday, eliminating the Royals from the playoff hunt.
It was the second straight night the Mariners shut out Kansas City as the teams ahead of the Royals in the wild-card race Tampa Bay, Cleveland and Texas won. The Royals haven't scored since the 12th inning of Monday's 6-5 win.
"Back-to-back shutouts, you're not going to win any games scoring zero runs," Alex Gordon said. "It's kind of a tough way to go out."
Mariners catcher Mike Zunino homered twice, Michael Saunders also homered and Kyle Seager hit a two-run double for Seattle, which has won three of four.
Zunino and Saunders hit back-to-back homers with two outs in the eighth inning, the 14th time this season Mariners have hit consecutive home runs.
The Royals entered Wednesday four games behind Cleveland for the second wild-card berth with five games to play and needed a victory.
Iwakuma made sure they didn't get one.
"We put ourselves in the situation to maybe find a way to sneak in, but we just came up a little short," Gordon said. "It's unfortunate, but we've got four more games and we're going to try to finish the season strong."
Iwakuma (14-6) finished his season without allowing a run in three straight starts, a streak of 23 scoreless innings.
Against the Royals, he gave up four hits and never allowed more than one base runner in an inning. He didn't walk anyone until the eighth. He had nine strikeouts, the 13th time in 33 starts he struck out at least seven.
"He handcuffed us, we couldn't do anything," Royals manager Ned Yost said.
Iwakuma's 2.66 ERA is third-best in the American League, and he finishes the season 4-0 in his final eight starts.
"It sort of caps off the year he had," Zunino said. "He just keeps getting stronger. Every start is getting better and better."
Ervin Santana (9-10) matched Iwakuma and kept the Mariners scoreless for the first four innings before Seattle broke through. Santana went six innings, allowing four runs and five hits with two strikeouts and four walks.
Zunino broke the scoreless tie leading off the fifth inning, taking Santana's first pitch deep to left field.
The blast sparked more scoring for the Mariners. With one out, Brad Miller doubled and Nick Franklin walked. With Seager at the plate, Santana's pickoff attempt to second ended up in center field, putting runners on second and third. Seager then laced a double down the right field line to give Seattle a 3-0 lead.
The Mariners added a run in the seventh. Dustin Ackley led off the inning with a double, and Yost walked out to the mound to signal Santana's night was done.
"I just told him, 'You know Erv, you had a great year. Real proud of you.' That was it," Yost said.
Miller pushed a bunt up the first base line and reliever Will Smith's throw to first baseman Eric Hosmer was wide, allowing Ackley to score.
The Royals' best offensive chance came in the fifth, when Mike Moustakas doubled with one out and took off running when Jarrod Dyson hit a line drive which looked as if it might reach the outfield.
Instead, Miller at shortstop timed his jump and snared the ball, then jogged to second to double off Moustakas and end the inning.
The Royals, who were six games below .500 at the All-Star break, head to Chicago to finish up the season with a four-game series against the White Sox.
Even without a shot at the playoffs, Kansas City (83-75) is assured of its first winning season in a decade, and one more win will give them their best record since they finished 84-78 in 1993.
"We've had a real good second half," Billy Butler said. "We have one more series and we get to build on this for next year. We had a good run, and the guys in here played hard."
Yost said he'll have a chance to give some young players an opportunity over the final four games, but doesn't expect any letdown despite no longer having a shot at the postseason.
"I think we've made a lot of progress as an organization," Yost said. "It was a giant step forward for us, and it was a step we definitely needed to take this year."
NOTES: Seattle manager Eric Wedge said before the game he feels like he's "hanging out there" with little clarity regarding his future with the organization. Wedge's contract originally a three-year deal expires after the season and Wedge indicated he's been given no word about whether he'll return for a fourth year. ... Seattle has hit 183 home runs this year, tied with Toronto for second-fewest in the major leagues. ... The last time Kansas City was shut out in back-to-back games was May 22-23, 2009, at St. Louis.