KANSAS CITY, Mo. — Even in defeat, Casper Wells could find plenty of positives to take out of another night when the Mariners again did some damage at the plate.

Beating up on some of the junkyard pitchers tossed their way by the Kansas City Royals the first two nights of this series apparently has had some carry-over. And so, despite an 8-7 Mariners loss Wednesday night on a Billy Butler walkoff home run in the ninth, Wells feels some of what he again saw from an offense that fought back all game long bodes well.

"I think we had solid at-bats all-around," he said. "There were a couple of tough pitchers we faced in some situations and we came through, we battled back. I mean, you want to come away with a victory, but it's nice knowing you can come back from that kind of deficit.

"It's definitely momentum-building and confidence-building from that type of perspective."

Wells had already brought the Mariners back from a 3-1 deficit with a two-run homer in the fourth off Royals veteran Bruce Chen. After Seattle starter Kevin Millwood fell behind 7-3 in the middle innings, the Mariners again made a game of it late.

They got a run in the sixth when Miguel Olivo's single scored Wells, who had reached base on one of his three hits. Then, in the seventh, Wells singled with Ichiro on base and moved up on a fielding error to put runners at second and third.

Jesus Montero singled to score both runners and make it 7-6. Kyle Seager then tied it up with a double to right field, giving him 33 two-out runs batted in this season to tie for the big-league lead.

Seager had notched another two-out RBI in the second with his solo homer off Chen.

The Mariners entered the night with the third-highest runs-per-game average on the road in the majors at 4.96, and bumped it up to 5.00. That trails only the Yankees (5.05) and Mets (5.02).

By comparison, the Mariners average just 2.86 runs per game at home — worst in the majors.

Seattle nearly scored more in this one as Brendan Ryan aggressively legged out a triple in the bottom of the eighth, then took off toward the plate on contact on a ball hit to the right side. The throw home was in the dirt and Ryan beat the throw and tag, but replays showed his front foot was in the air and never actually touched home plate.

He was called out by plate umpire Jim Joyce.

"That's a pretty special call," Ryan said when told what the replays had shown. "I don't really know what to say. That's crazy."

Ryan said he had little hesitation going for the triple instead of the double, or trying to score on the grounder.

"If they're going to be perfect, fine," he said of the triple. "But if not, we have a chance to win the game without a base hit."

Instead, the game remained tied. It stayed that way in the bottom of the eighth, too, largely because Ryan ranged far to his right to snag a grounder by Alcides Escobar that was headed toward left field.

A run likely would have scored had the ball gotten through, but the resulting infield single forced lead runner Alex Gordon to halt at third. The Mariners escaped on an ensuing ground out.

In the ninth, seldom-used reliever Josh Kinney left a sinker over the heart of the plate and Butler crushed it deep into the night in left-center.

"I was obviously trying to keep the ball away from that guy," Kinney said. "If he's going to do that, you want him to hit it to right field. And the ball just ran back right over the plate. It ran back over and sometimes you've got to tip your cap. It was a strike and he's supposed to hit it."

Mariners manager Eric Wedge didn't have Brandon League or Lucas Luetge available to pitch and was saving Tom Wilhelmsen for a possible closing situation. Wedge chalked up Millwood's rough night — seven runs in five innings — to some hard-luck on grounders that sneaked through the infield.

There was also a long double to right-center in the second by Mike Moustakas that seemed to hang in the air for an eternity after Ichiro appeared to get a slow read on it. The ball eventually scored a run and help set up two more as the Royals took a 3-1 lead.

But the Mariners never stopped fighting back. They'd begun the night with three strikeouts against Chen and five consecutive outs before Seager's homer got the ball rolling.

"The guys swung the bats well again today," Wedge said. "There was a different type of pitcher on the mound and that was evident early on. But I felt like our guys did a good job of making some adjustments, getting to him and making it work."

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