A long wait deserves a long home run. And even in defeat, Adalberto Mondesi’s seventh-inning solo shot Monday night at Progressive Field was worthy of a longer look.

While the projected distance of the 458-foot blast didn’t enhance its worth in the runs column -- where Kansas City was outpaced, 5-2, by Cleveland for its seventh consecutive defeat -- the homer offered hope that a central figure of the Royals’ rebuild can end an otherwise abysmal offensive campaign on a positive note.

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Mondesi’s homer was the longest of his career and the longest at Progressive Field this season, per Statcast. It took 192 at-bats to get to those 458 feet, so the length was vast in multiple senses. Mondesi’s .499 OPS is the lowest among all Major League qualifiers. But in recent days the Royals have seen more confident at-bats and more reasonable results.

“His eyes and his body and his swing seem to be working well together,” said manager Mike Matheny, “where he’s behind the ball and not jumping as much.”

The Royals have scored just 18 runs in a losing streak that covers 11.7% of this 60-game season. So you’d better believe they’re looking for positives.

Monday didn’t offer many. Brad Keller’s strong stuff resulted in a bunch of weak singles that squeaked through, leading to five runs (four earned) in 6 2/3 innings for what he called “probably the most frustrating outing of my life.” The Royals didn’t help him much offensively or defensively.

Mondesi, though, continued a recent uptick in output. He had a three-hit night against the White Sox on Friday, and on Sunday he legged out his first extra-base hit in 86 at-bats with a bloop double. That he was able to do anything of note Monday against Tribe starter Zach Plesac, who now has a 1.83 ERA in six career starts against the Royals, was significant.

In the fifth inning, Mondesi swiped second after grounding into a forceout for his 100th career steal and MLB-leading 11th of the season. This came mere hours after Matheny, in a conversation about the late, great Lou Brock, singled Mondesi out as the rare talent who can be elite from both a speed and power standpoint.

“That’s why Mondi’s one of those special players,” Matheny had said. “We celebrate what he can do and will end up doing.”

It was a 3-0 game in the seventh when Mondesi worked the count to 3-1 and then turned on Plesac’s 92-mph four-seamer. Having come into the game with a .329 slugging percentage off fastballs that is among the lowest in the Majors, Mondesi needed this one -- and he got all of it. The ball sailed into the deserted right-field concourse, landing near a sauerkraut stand.

“Oh man,” Keller said. “He blistered that one.”

Mondesi was limited to 102 games last year by shoulder and groin injuries, yet still managed to hit 20 doubles and a Major League-leading 10 triples with 43 stolen bases. It’s enticing to think what he might do in his first complete season in the bigs. But only recently has the bat awoken.

In hitting a home run, Mondesi did what nobody has been able to do off Keller this year. And Keller has still only allowed one extra-base hit in six starts this season, though mark that down as a technicality. In the sixth inning of this game, Carlos Santana did manage to double off Keller. But a baserunning blunder by Francisco Lindor, who missed second base on his way to third on the play, led to that being ruled a fielder’s choice instead of a two-bagger. After the play had concluded, Keller tossed the ball to second, and Lindor was ruled out.

What might have been a pivotal play proved inconsequential, due to the Royals’ continued offensive rut. It’s worth noting, though, that the reason Lindor was confused on that play is because he was deked by Mondesi.

Monday, therefore, was a reminder of the way Mondesi can impact a game in all facets. Even in striking out looking for the final out against Cleveland closer Brad Hand, Mondesi left an impression on his manager by fouling off four tough pitches. In the midst of a Royal rut, these signs of life from the shortstop are meaningful.

“It’s going to be fun whenever he gets hot,” Keller said. “We can see it coming.”