Jason Vargas had heard the applause building behind the Mariners dugout as he headed off the field following eight innings of one-hit ball.

Vargas had thrown 115 pitches already and the fans knew he wouldn't be needed in the ninth inning of this 4-1 win over the Kansas City Royals. But those doing the cheering weren't focused only on Thursday night's clash; not with this being the final start for Vargas before next week's trade deadline and his name continuing to draw interest around the game.

And just like those fans, Vargas also knew he might have just exited the field in a Mariners uniform for the final time. But just in case it's still up-for-discussion and not a done deal, he had one thing to say to his current team while it's still just that.

"I hope," he said, "that I've proven I'm worth more here."

Only time will tell whether the Mariners view a pitcher who won his career-high 11th game as being worth more to them in their uniform than in someone else's. Vargas is said to be drawing trade interest because he's offered up steady results, delivered lofty innings totals and costs a whole lot less than other pitchers thought to be on the market.

But his $4.8 million salary could come close to doubling in arbitration as his wins pile up, his earned-run average falls and his innings totals remain high. Arbitrators tend to buy into more traditional baseball statistics as opposed to the newer sabermetric variety, and Vargas, on the surface, is in for a hefty payday.

The Mariners might feel it's too big a payday for a rebuilding team that already has more than $20 million committed to Felix Hernandez next season and needs more offense. And if that's the case then the argument to deal him now grows stronger.

But don't tell that to the Safeco Field crowd of 15,014 that cheered him as he left the field Thursday night. Vargas had retired 11 in a row to start the game before issuing a walk and then the 200th double of Billy Butler's career to score the only run he would allow on the only hit he would give up.

He would go on to retire nine of his final 11, walking a pair in the interim, and ride some unusually potent Mariners offense to victory. Just as they had in Kansas City last week, the Mariners took early advantage of an erratic-looking starter as Luis Mendoza yielded a two-run single to Mike Carp in the first inning.

It was the first of three hits on the night for Carp, hitless in the previous two games since returning off the disabled list.

"It's just about getting at-bats and getting it going again," Carp said. "I never really got a chance to get going this season and I've got two months to try to prove something."

Other struggling players followed suit against Mendoza as Dustin Ackley snapped an 0-for-20 slump with a single and double his first two times up. Miguel Olivo, batting .198 to start the game, added a single and a sixth-inning double as well.

And the now-.171-hitting Carlos Peguero, who'd gone 0-for-12 as Ichiro's replacement in right field, came through as well with a double down the right-field line to score Olivo in that sixth.

It was all academic by the time Tom Wilhelmsen came in and got the one-inning save in the ninth.

Vargas smiled as his personal wins milestone was achieved following an injury-plagued start to his career with the Florida Marlins and New York Mets.

"This has been my first home in the big leagues," Vargas said. "I was given a lot of opportunity here and I'm fortunate I took advantage of it."

Vargas took advantage even more this month, going 4-0 with a 1.46 earned-run average after honing his fastball and fine-tuning his change-up delivery. The results have seen him slow his major-league worst total of 25 home runs allowed — 19 of those on the road.

"He's just grown," Mariners manager Eric Wedge said. "Even in the short period of time I've been here. It's been a lot of fun to watch this guy continue to figure it out and continue to get better."

Wedge said Vargas has learned to identify the crucial "two or three times" in games where pitches need to be executed. Vargas chalks it up to continued experience. And now that he's had the experience with Seattle, he says he's not quite ready to let it all go.

"This is a great city," he said. "I love my teammates. I love the organization and the staff. It's home to me."

Geoff Baker: 206-464-8286 or gbaker@seattletimes.com.

On Twitter @gbakermariners