Before you ask, Jackson Jobe isn't joining the Detroit Tigers in September for his MLB debut.

For what it's worth, Jobe — the top pitching prospect in baseball — didn't even complete two innings in Friday's start with Double-A Erie. The 22-year-old, a hard-throwing right-handed strikeout machine, was so frustrated at his poor performance that he threw his glove and his hat into the dugout while walking off the field.

The Tigers, meanwhile, are gearing up to increase their active roster from 26 players to 28 players for Sunday's game against the Boston Red Sox at Comerica Park, as MLB rosters expand by two players for the entire month of September.

Justyn-Henry Malloy, a 24-year-old designated hitter, is expected to be one of the two promotions, with the other being a pitcher. He hit .217 with eight home runs, 21 walks and 74 strikeouts in 57 games with the Tigers after making his MLB debut in early June.

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The Tigers made three roster moves before Friday's game, headlined by right-hander Casey Mize returning from the injured list and left-handed reliever Joey Wentz getting designated for assignment. The Tigers also transferred right-handed reliever Alex Faedo to the 60-day injured list with a right shoulder strain, which ends his season.

The Faedo move leaves the Tigers with 39 players on the 40-man roster.

"There's always moves on the horizon," manager A.J. Hinch said before Friday's 7-5 loss. "It's just a matter of when and what and where. But nothing to comment on."

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To clarify, the Tigers don't have anything imminent planned for the 40-man roster, meaning the open spot probably isn't anything more than flexibility for a waiver claim in the future. Again, Jobe isn't filling the open spot on the 40-man roster.

When rosters expand, the Tigers are planning to promote from players already on the 40-man roster. If that holds true, right-handed reliever Ricky Vanasco is the only available option on the pitching side, while Malloy, outfielder Akil Baddoo, infielder Eddys Leonard, first baseman Bligh Madris and outfielder Ryan Vilade are options on the position player side.

Two injured players — right-hander Reese Olson (right shoulder strain) and outfielder Wenceel Pérez (left oblique strain) — won't be healthy in time for Sunday's call ups. Both players need to complete rehab assignments with Triple-A Toledo, which should begin within the next few days.

On the pitching side, Vanasco is the only healthy and eligible candidate from the 40-man roster to join the Tigers. The Tigers recently optioned left-handed reliever Bryan Sammons and right-handed reliever Mason Englert to Triple-A Toledo, making them ineligible to return for 10 days following their options.

Vanasco, whom the Tigers acquired from the Los Angeles Dodgers for cash considerations in late July, has a 1.38 ERA with seven walks and 15 strikeouts in 13 innings since joining Triple-A Toledo. The 25-year-old made his MLB debut back in mid-April with the Dodgers. Vanasco thrives on throwing his high-velocity fastball at the top of the strike zone, but he doesn't get a lot of chase with his curveball and slider, which ultimately leads to too many walks.

The Tigers could always pivot to a non-roster pitcher, such as right-handed reliever Chase Lee from the Andrew Chafin trade, because of the open spot on the 40-man roster, but it sounds like the Tigers aren't planning to do that. Lee, though, needs to be added to the 40-man roster by mid-November to protect him from the Rule 5 draft in early December.

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On the position-playing side, the Tigers have many candidates to join the roster, headlined by Malloy.

Malloy had an above-average 10.3% walk rate in his first stint with the Tigers, along with an elite 19.1% chase rate, but he had below-average marks in average exit velocity (86.9 mph), whiff rate (36.2%) and strikeout rate (36.3%). He didn't chase bad pitches, but he also didn't make enough in-zone contact. On defense, Malloy was a liability in the left field and spent most of his time as the designated hitter.

But Malloy played left field in seven of 10 games in Triple-A Toledo after the Tigers optioned him Aug. 19. He has spent exactly 12 days with the Mud Hens, which makes him eligible to return to the Tigers.

As for Jobe, the former No. 3 overall draft pick has the best repertoire of pitches in the Tigers' farm system, but he still has a lot of work to do. He owns a 2.65 ERA with 20 walks and 28 strikeouts across 34 innings in his last seven starts for Double-A Erie.

That 13.5% walk rate isn't going to earn him a promotion.

And don't forget, the Tigers want Jobe to pitch in Triple-A Toledo before making his MLB debut.

Contact Evan Petzold at epetzold@freepress.com or follow him @EvanPetzold.

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This article originally appeared on Detroit Free Press: Detroit Tigers' Justyn-Henry Malloy headlines call-up candidates