Kansas City, Mo. ? Casper Wells walked back to the dugout after belting a three-run homer in the first inning and a two-run triple in the second and was already hearing it from his Seattle teammates.

The toughest two legs of the cycle were in the books.

Piece of cake from here, right?

“It was like, geez, thanks guys,” said Wells, whose five RBIs in the first two innings of the Mariners’ 9-4 victory over the Kansas City Royals on Monday night were a career high.

“Do you tell a pitcher when they’re throwing perfect game, ‘Hey, you’re throwing a perfect game?'” Wells said with a smile. “It’s like, ‘Hey, thanks.'”

Wells couldn’t manage a hit in his next three at-bats, though the Mariners hardly needed any more offense. They had already battered Royals starter Jonathan Sanchez for seven runs in 1 1/3 innings and were on their way to their best output since June 20.

Justin Smoak also had a two-run homer off Sanchez (1-6), Ichiro Suzuki added an RBI triple and Dustin Ackley homered to pace one of the worst offenses in the American League.

“I loved the way they turned around some fastballs,” Seattle manager Eric Wedge said. “If you want to be a good big league hitter, you have to turn around some fastballs.”

Or whatever else Sanchez was throwing.

Jason Vargas (9-7) took advantage of Seattle’s instant offense, giving up homers to Salvador Perez and Billy Butler but still lasting six shaky innings to win his second straight game.

Vargas went the distance in beating Oakland just before the All-Star break.

“When your offense comes out like that,” he said, “you shouldn’t blow the lead.”

Acquired this past offseason for outfielder Melky Cabrera, the MVP of the All-Star game at Kauffman Stadium just last week, Sanchez has been nothing short of abysmal all year.

He hasn’t gone past the sixth inning since May 28, 2011, and hasn’t allowed fewer than four runs since early June. His already-bloated ERA rose to 7.76, and he’s drawn the ire of Kansas City fans for his almost nonchalant attitude during and after his outings.

“When you work four days in a row to make a start and it doesn’t work, it’s kind of frustrating,” Sanchez said. “What can I say? I’ve got to look forward and see what happens.”

Sanchez didn’t even give fans a chance to get comfy Monday night.

He walked Ackley on five pitches to start the game, and then watched Suzuki dump a single into left field before Wells belted a three-run homer to left. Jesus Montero added a single and Smoak hit his two-run shot, giving the Mariners a 5-0 lead after just five batters.

Sanchez retired the next batter to get through the inning, but gave up another base hit to Brendan Ryan leading off the second. Ackley added a single and Wells a two-run triple, giving Seattle a 7-0 lead and sending Sanchez on the slow trudge back to the dugout.

He still hasn’t won since his Royals debut on April 8.

“They jumped on a couple of high fastballs for home runs in the first,” Royals manager Ned Yost said. “It’s one of those games where they were on him, put seven runs up early and there’s not much we could do.”

All that offense came from a Seattle lineup that came into the night second-to-last in the AL in homers, runs and team batting average (.229), and last in OBP and RBIs.

Perez homered to help Kansas City crack the scoreboard in the third inning, and Butler’s two-run shot with two outs gave the Royals’ sullen fanbase reason to hope — at least for the precious few minutes before Seattle came to the plate in the fourth inning.