SEATTLE -- His arrival in a minor trade during the Mariners’ first homestand of the season barely made a ripple. But among the multitude of deals struck by general manager Jerry Dipoto this year, the acquisition of catcher Tom Murphy is beginning to look better and better.

The 28-year-old Rockies castoff clubbed his sixth home run in his past eight games on Monday, a three-run shot in the fifth inning of the Mariners’ 6-4 loss to the Royals at T-Mobile Park.

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Murphy went 2-for-4 with two runs and three RBIs, lifting his average to .300 with eight homers in 27 games. While splitting time with starting catcher Omar Narvaez, Murphy already is closing in on the 10 homers he totaled in 81 games over four seasons with the Rockies while posting a .219 average.

“Murph has played really well,” Mariners manager Scott Servais said. “From Day One coming in here, we talked about the adjustments he wanted to make and was willing to make. He’s worked his tail off and is a totally different hitter now than when we acquired him.

“And that’s a credit to him for being open to making the adjustments and finding something that works for him. His approach is really good at the plate right now. He’s on almost everything and quality at-bats every time he’s out here, it seems like.”

Murphy has hit .333 (10-for-30) with six homers and 14 RBIs in eight starts since May 31, and his latest long ball was a 430-footer to left with a 109.6 mph exit velocity.

“Things are just kind of coming together,” Murphy said. “I’m very appreciative for all the work in the cage the hitting coaches have been putting in with me. Those guys are some of the best I’ve ever had in my life. Coupled with the approach and plans we have between our analytics and the hitting coaches, it’s not hard to understand why people improve over time.”

Murphy’s blast gave Seattle a 4-2 lead and a shot at its first back-to-back wins since twice topping the A’s on May 13-14, but the Royals rallied late as Jorge Soler and Martin Maldonado homered off Mariners relievers in the final two frames.

The Mariners are 4-1 this year against the Royals, having swept a four-game series in Kansas City in mid-April that hiked the Mariners’ record to 13-2.

Since then, Seattle has gone 18-43 to drop to last place in the American League West at 31-45, while the Royals are last in the AL Central at 24-48 and an MLB-worst 10-25 on the road.

After “opener” Tayler Scott gave up a pair of runs while getting just two outs in the first, veteran lefty Tommy Milone shut down the Royals on three hits and one run in 6 1/3 innings. But Kansas City regained the lead on a two-run bolt by Soler off Anthony Bass in the eighth and added an insurance run when Maldonado went deep off Gerson Bautista in the ninth.

The 32-year-old Milone is 1-1 with a 3.03 ERA in six games since replacing rookie Erik Swanson in the rotation. He’s found increased success pitching up in the zone this year, even with a fastball that runs in the 88-89 mph range.

“That’s something I kind of started doing last year and I’ve embraced it just because the analytics now tell you where your pitches play,” Milone said. “For me, I had a higher spin rate and the fastball plays up in the zone a little better. Obviously I’m not going abandon staying down because that’s primarily where a pitcher like me needs to be, but to work the ball up in the zone as well has definitely helped.”

Opening act still auditioning

Scott -- the first South African to pitch in the Majors -- was the latest Mariners reliever to get an opening bid, and his struggles continued a troubling trend.

It was the sixth time the Mariners have tried the opener strategy this season -- all in the past two weeks -- and the results have been a combined 18.56 ERA with 11 hits, 11 runs, eight walks and five strikeouts in 5 1/3 innings while the team has gone 2-4 in those games.

The plus side has been that the “bulk” pitchers who have followed the openers have gone 1-0 with a 3.93 ERA, including three strong outings now by Milone in that scenario.

But three of the six “openers” have allowed three runs, Scott allowed two runs in his first shot and twice the result has been a scoreless first.

The plan was put into place after Seattle’s starters went through a particularly rough stretch in May and Felix Hernandez’s injury left the club with four left-handers in the rotation.

Trying to give opponents a different look and see if the opener experiment that has worked well for the Rays and several other clubs might help, Seattle has now tried four different relievers in the opener role -- Austin Adams, Gerson Bautista, Cory Gearrin and now Scott.

“Finding that guy that can go out and throw a zero up there has been a challenge,” Servais said. “I still believe in the opener. You’re trying to win the game and manage the game. I know it’s a little different for most fans to grasp hold of it, but seven innings, three runs, we’ll take that every night. You think you’re going to have a really good chance to win the game and we were in a great spot to win it, we just didn’t get it done.”