KANSAS CITY -- The homestand that was supposed to provide a launching pad for the Royals into serious postseason contention instead may have sealed the defending World Series champions' fate.
The A's completed a four-game sweep with a resounding 14-5 victory on Thursday night, outscoring the Royals, 43-12, in the series. Oakland's Joey Wendle notched his first four-hit game, and fellow rookie Ryon Healy had three hits, including a mammoth three-run homer that cleared the fountains in left-center field at Kauffman Stadium. Marcus Semien also hit a three-run homer for the A's.
"I think a lot of it has to do with some of the younger guys that are here and playing hard and rubbing off on everybody else, and trying to make a name for themselves at the big league level," A's manager Bob Melvin said. "We played real well in all facets. Got some leads, kept adding on, got good pitching. We did everything as right this series as we've done all year."
The loss reduced the Royals' elimination number from American League Wild Card contention to 11, as they dropped six games behind Wild Card holders Baltimore and Toronto.
Right-hander Daniel Mengden, who was 1-7 with a 6.39 ERA entering the game, silenced the Royals on three hits through seven innings. He walked none and struck out six.
"Everything was just perfect for him tonight," catcher Stephen Vogt said. "It was a huge performance for him personally and for the team. He pitched great, and it should be a big confidence-builder for him going into his last couple starts."
The series provided the best run differential (31) in a four-game series in Oakland history (previous mark was 27 against Seattle on April 17-19, 1981). The Royals also set a record for most runs allowed in a four-game set with 43. The previous mark was 41, set in 1998 vs. the Yankees, and in 2006 vs. the Twins.
Royals infielder Christian Colón hit his first Major League home run, a three-run shot in the ninth inning. He had gone 292 at-bats without one.

"It felt good off the bat," Colon said. "I didn't feel anything. I wish it was under different circumstances. But it was a big monkey off my back.
"It's been tough [this series]. We're not used to this [losing]. It's hard to enjoy [the home run]."
MOMENTS THAT MATTERED
The blast: Healy seems to keep finding ways to wow the A's. The rookie third baseman's third-inning moonshot was quite the spectacle, traveling over the left-field fountains a Statcast-estimated 480 feet. It's the fifth-longest homer recorded in the Majors this season and second-longest not hit at Coors Field. The hot-hitting Healy, who began the season at Double-A Midland, has 10 homers since his July promotion, including four in his last eight games.

"Once they told me the distance," Healy said, "I don't think I've hit one that far in my life."
"I was screaming my head off," Vogt said. "He's been so locked in lately."
First big league hit:Hunter Dozier, the Royals' first-round pick in the 2013 Draft, recorded his first Major League hit with a double in the ninth. Moments earlier, they ended a 17-inning scoreless streak with Tony Cruz's sacrifice fly.

"I faced [Dillon] Overton in Nashville [at Triple-A]," Dozier said. "I know he had a good fastball and good changeup. I was just looking to hit a fastball early, and he gave me one. I put a good swing on it. Just wanted to hit something hard."
It's contagious: The A's racked up 16 hits in the finale, bringing the grand total in this series to 52. Up and down their lineup, contributions poured in, starting with Wendle, whose four-hit game gave him 14 hits in his last 10 contests. Elsewhere, Vogt notched five RBIs, while Semien capped a productive series with a three-run homer and a run-scoring double, giving him 10 RBIs in this four-game set. Healy, meanwhile, fell a triple shy of the cycle. The 43 runs set an Oakland record for most in a four-game series.

"We haven't put up offensive numbers like that all year," Semien said. "We've been on the other side of it and seen how fun it looks. Now, we know we're capable of that. It's not going to happen every series, but when it does happen, you want to figure out what you're doing right, stick with it and hopefully finish strong."
"The thing that I really liked about these four days is we didn't stop," Vogt said. "We just kept going, and that's something we haven't done really well this year. I can't emphasize enough what Joey Wendle did this series, just getting on base a lot and sparking our offense every time we turned it over. He really got us going."
Tough night: Right-hander Edinson Vólquez started for the Royals and retired the first five hitters he faced. But Volquez never made it out of the fourth inning. He gave up seven hits, nine runs (eight earned) and walked four, while his ERA rose to 5.40.
"Been watching videos and trying to get better the whole year," Volquez said. "It just hasn't worked the whole year. But I'm not going to quit. I'm going to go out and try hard these last [few] starts. I feel good [physically]. I feel strong."
WHAT'S NEXT
Athletics: Right-hander Kendall Graveman gets the ball on Friday at 5:05 p.m. PT when the A's open a three-game series with the Rangers at Globe Life Park. Graveman is looking to rebound from his worst start of the season, a five-inning, eight-run outing against the Mariners after posting a 2.82 ERA in his previous 12 starts.
Royals: Right-hander Ian Kennedy (11-9, 3.62 ERA) takes the mound on Friday at 7:15 p.m. CT when the Royals begin a four-game wraparound series against the White Sox at Kauffman Stadium. Kennedy was terrific against the White Sox on Sunday, throwing six shutout innings while giving up just one hit in a 2-0 win.
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