For the second straight start, Justus Sheffield took the hill against a struggling American League Central opponent, and for the second straight start, he was hit hard.

In an up-and-down season for the 25-year-old left-hander, Wednesday’s 7-2 loss to Minnesota turned out to be one of his toughest outings. He surrendered a career-high seven earned runs and gave up 10 hits for just the third time, all coming this season.

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“It sucks. It definitely sucks,” Sheffield said. “I want to go out there and I want to pitch well, and I want to go out there and compete and win ballgames for my team. I think that's the most frustrating part right now, is just letting down the team.”

More glaring was the type of contact the Twins were tagging him for -- so much of it was off the bat loud and large, the biggest of which came from Boomstick, former Mariner Nelson Cruz, who crushed a three-run, 421-foot homer into the second deck in the fifth inning that put the game out of reach.

Half of the 20 batted balls against Sheffield were off the bat harder than 95 mph, the threshold that Statcast classifies as hard-hit, with the Cruz bomb (112.3 mph) and a single from Miguel Sanó (112 mph) standing out. Overall, Minnesota had an average exit velocity of 95.6 mph, essentially a hard-hit ball every time they made contact. That’s the hardest such average for any of Sheffield’s career starts.

That’s a tangible way to outline that Sheffield’s struggles are illuminating -- mainly because it looked the same as his last time out in Detroit on Thursday, when the Tigers averaged 95.2 mph off the bat.

So, what’s the root of the issues?

Sheffield is a three-pitch starter who relies heavily on his hard-sweeping slider, which when it’s on, is elite. Then he has the two-seam fastball (also tracked as a sinker) that he opted for last season for its behavior and spin, and the evolving changeup, which at times has looked sharp. But the Twins were 3-for-7 against the change on Wednesday, including a booming homer from Ryan Jeffers in the fifth on one that was middle-in without much deception.

But it starts with fastball location.

“You’ve got to live at the bottom with Sheff,” Mariners manager Scott Servais said. “Some of our guys can live at the top of the strike zone, but not him. And it's the sink, the ball that's down. He usually keeps the ball on the ground, and that wasn't the case so much tonight.”

When he’s off with one -- or worse, more -- of those offerings, things can spiral quickly. And that becomes even more exacerbated when location evades him, as it did on Wednesday.

More than anything, the Mariners say, it’s Sheffield’s fastball location. Too often lately, he’s leaving those heaters over the heart of the plate. But they are attempting to combat the issue by instituting a minor mechanical adjustment, though it’s one that could take time and patience.

“It's just getting back to the basics,” Sheffield said. “I think I got in a bad habit kind of throughout the season of just not really repeat mechanics. When they're on point, the ball comes out clean, and it usually goes where I want it to. But it's all about repeating the mechanics. And we'll see. I continue to work on it. I’ve been working hard this year, and I’ll continue to work hard.”

It’s also worth remembering that Sheffield, like many Mariners starters, is maneuvering his way through a 162-game season for the first time. Some of these adjustments and growing pains could be weathered over multiple outings. Wednesday marked his 12th start of 2021, and he’d never made more than 10, capped last year when he was one of the AL’s top rookies.

“He's a young pitcher that’s trying to find it,” Servais said. “He's going through a little bit of a rough patch, and he will get the ship righted. I feel very confident in that. Sheff is a super competitive guy.”