Cubs fans had long been clamoring for Owen Caissie – the team’s top minor leaguer and a top 100 prospect in all of baseball – to join an offense that has been scuffling mightily.

Pull up his stats at Triple-A Iowa and you understand – he has 22 home runs, 26 doubles and a whopping .955 OPS. Narrow it down over his last 52 games, and those numbers look even more gaudy – .332/.426/.653 slash line (1.079 OPS) with 15 home runs, 33 RBI and a 175 weighted runs created plus, 75 percentage points better than league average.

Of course, part of the equation in calling him up is roster space. Caissie was already on the 40-man roster, but Miguel Amaya’s sprained ankle that he suffered on Wednesday night created an opening on the active roster.

But, on the field, the jump from the highest level of the minor leagues to the majors is massive, and there’s more than just traditional stats that the Cubs front office looks at when deciding when to give a prospect that first call-up.

“I think the biggest thing is his in-zone whiff has really gone down,” Cubs assistant general manager Jared Banner told reporters in Toronto before Thursday’s series finale against the Blue Jays. “I think that’s a really telltale sign for him being ready to step up to the next level.”

That’s because, given Caissie’s power, you want him making contact on pitches in the zone – a simple concept, but one that’s easier said than done. As a player ascends the minor league ladder, the pitching improves – pitches that start in the zone have a bit more cutting action or ride more in the zone and can cause hitters to miss. Caissie was making more contact on those pitches, and with his prowess, that leads to more results, as the last 52 games showcase.

The results weren’t quite there in his debut – he finished 0-for-4 with three flyouts and a strikeout in the Cubs’ 2-1 loss to the Blue Jays – but his first major-league at-bat was a 93.8-mph liner that produced a nice diving catch from Davis Schneider in left field for an out. It’s a reminder, too, that Caissie might not provide the instant impact Cubs fans might have hoped for given his Triple-A prowess.

[Watch every Caissie at-bat from his MLB debut in Toronto]

The adjustment to the majors is difficult; Amaya, Pete Crow-Armstrong and Matt Shaw have all undergone their struggles in the big leagues over the last two seasons before finding their footing offensively. Caissie might have a few more of those 0-for days at the plate, but the Cubs clearly believe he can still be a useful player while he’s up with the big-league club.

He’ll serve as an outfield option for Cubs manager Craig Counsell while he’s up in Chicago. The Cubs currently have four outfielders on the roster – Crow-Armstrong, Ian Happ, Kyle Tucker and Seiya Suzuki. Suzuki has served as the team’s primary designated hitter, and utilityman Willi Castro, who manned center field in Thursday’s finale, can play across the pasture, too.

But if the Cubs want to give any of the four outfielders a day off, like they did with Crow-Armstrong on Thursday, Caissie can help fill a void. That’s crucial as the Cubs are amidst a 14-games-in-13-day stretch. Having options will be paramount.

And this experience could help him long-term, as they hope he reaches his potential.

“I think offense is his calling card, and he hits the ball extremely hard,” Counsell told reporters in Toronto on Thursday morning. “I think he’s going to hit a lot of home runs someday, [but] he’s not a home run hitter right now.

“I think he’s just a good all-around hitter, good plate discipline, hits the ball hard.”