SEATTLE -- Conversion counts, those that greatly dictate the outcome of an at-bat, are at the center of Jorge Soler's hitting approach. Winning the 0-0 count, the 1-1 count have been paramount to the Royals’ slugger blossoming into the elite power hitter many envisioned he’d become, even if it took longer than anticipated.

Soler crushed a 1-1 slider from Mariners reliever Anthony Bass that was off the plate, and dispensed it 396 feet to right field for a two-run go-ahead homer that lifted the Royals to a 6-4 win on Monday at T-Mobile Park.

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Everything about the homer -- the count, the pitch type, the location -- is reflective of how Soler has polished himself into one of the American League’s top power hitters this season, the Royals say. The homer was Soler’s 19th, just two shy of Mike Trout for the AL lead.

“I was just getting a lot of offspeed pitches lately and I was just trying not to fly open, trying to go the other way,” Soler said through interpreter and Royals quality control coach Pedro Grifol. “I just followed the pitch and tried to drive it the other way. … I'm spending a lot of time creating an approach, and it's been working for me. I feel prepared for the ballgame.”

Soler’s ability to execute against secondary pitches remains a work in progress. Entering Monday, Soler was hitting .301 against fastballs and .199 against anything else, and for his career, he was a .181 hitter against secondary pitches. But the club says that Soler’s pitch-identifying ability has improved naturally through six seasons in the Majors, and he’s supplemented that by studying daily with Grifol, who outlines opposing pitchers’ tendencies through charts, video and other scouting reports.

“He's got to win the conversion counts, and when he does, he's got to be able to hit non-fastballs as good as he hits fastballs, which is pretty good,” Grifol said. “The [homer] he hit today was a slider, off the plate a little bit, but he's got some long extremities and he was able to cover the plate. He's got to be able to hit offspeed pitches, too, that are strikes.”

“He's just becoming more experienced. Understanding his tools and abilities,” Royals manager Ned Yost said. “He's tremendously strong. I think he's gotten the coaches -- Pedro and [hitting coach] Terry [Bradshaw] have really done a good job of pushing him a little bit to be a little bit more aggressive. He knows the strike zone extremely well. He could be a little more aggressive. Don't let pitches that he can hit slide by.”

Of course, Soler is also benefiting from being healthy. Grifol points out that Soler was on a similar pace last year when his season was abruptly ended after just 61 games due to a fractured left toe sustained on June 15. Soler had a higher OPS in ’18, .820 to .811 entering Monday, but he’s already blown past his previous career high of 12 homers in ‘16 with the Cubs.

There was also a rough stretch during his first season with the Royals in ’17, where his offensive struggles became so prolonged that the club optioned him to Triple-A Omaha in July for nearly two months, which is why what he’s doing now has them encouraged for the long term. Because for a club that has been retooled four years removed from a World Series championship, the Royals believe they have pieces in place to return to contention -- and Soler, who is under club control through 2021, is a big part of that.

Pitching staff overcomes brief blunders

Soler’s shot spelled the Royals’ pitching staff of what would’ve been a tough-luck loss after Danny Duffy hung a slider to Tom Murphy that led to a three-run homer in the fifth, which looked like it would lead to an MLB-high 26th loss in a game that the Royals had led. Otherwise, Duffy pitched well over his first two trips through the Mariners' lineup over the first four innings.

Duffy, like the rest of the Royals, has seen opposing hitters’ success balloon the third time through the order (which is when the Mariners mounted a comeback in the fifth). Opposing hitters are slashing .264/.316/.528 against Duffy in those situations, and the Royals have given up an .897 OPS the third time through, fourth-highest in the Majors.

“Today, I had some really good stuff. It just wasn't where I wanted it to be,” Duffy said. “The guys saw me twice, all of them. It's a task for the pitchers the third time through the order, and I just wasn't able to command the fastball or anything after about one out in the fourth.”

The positives: left-handed long reliever Brian Flynn pitched a scoreless outing in his first appearance since June 6 against Boston. Since being activated off the injured list on May 25, Flynn has a 0.93 ERA over four outings. Lefty Jake Diekman tossed a scoreless eighth, and Ian Kennedy picked up his eighth save in 10 attempts, though he had to recover from back-to-back walks to lead off the ninth.