LAKELAND, Fla. -- Ron Gardenhire has spent countless days and nights over the years in Spring Training worrying about how best to put together a 25-man roster -- who stays, who goes, who fits. For the first time in his career, he’ll be fretting a 26-man roster when the Tigers prepare to head north in just over five weeks.

“My goal right away, when I first thought about it, was, ‘Boy, that’d be that third catcher, a third catcher that could play the outfield, infield, wherever.’ That would be wonderful. I’ve always said that a third catcher’s important. When you have two catchers, you’re always worried about pinch-hitting for the first one if you had to and then putting your last catcher in.”

That isn’t likely to happen, given the makeup of the Tigers’ camp roster. With John Hicks gone, the only catcher in big league camp who can play multiple positions is Brady Policelli, an All-Star super-utility player for Class A Advanced Lakeland who has yet to reach Double-A. He played everywhere but first base and pitcher over the last two seasons.

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So for now, the 26th man on the Tigers’ Opening Day roster is likely to be a utility infielder or outfielder. It’s a big reason behind the late offseason signing of Jordy Mercer, who moved around the infield in Detroit last September once Willi Castro took over at shortstop down the stretch. With Niko Goodrum expected to take over at short, Mercer will have to be versatile to make the Opening Day roster.

With Spring Training games set to begin later this week, here’s an early look at how the Opening Day roster could shake out:

Catcher
Lock: Austin Romine
Possibilities: Grayson Greiner, Jake Rogers, Eric Haase

Romine, a free-agent signing, is a lock to make the roster and has a good chance to get the bulk of the starts early, providing a veteran presence behind the plate. That impacts the battle for the other spot. While Rogers and his retinkered swing will get a long look in camp, the Tigers will want to ensure him regular at-bats to work on it. He’s more likely to get those at Triple-A Toledo for now. Greiner is best positioned for the other spot in Detroit, though Haase could crash the roster.

First base
Locks: C.J. Cron, Miguel Cabrera

These two are set at first, but it's a question of whether Cabrera can play any first base or is left to full-time DH duties.

Second base
Lock: Jonathan Schoop

The Tigers are counting on Schoop to bolster the offense in an everyday role.

Shortstop
Lock: Niko Goodrum
Possibility: Willi Castro

The time has come for Goodrum to get a chance to concentrate on one position. He was an early arrival at Spring Training this year to work with hitting coach Joe Vavra and infield coach Ramon Santiago. A strong Spring Training from Castro could alter the plan, but for now, the job is Goodrum’s to win.

Third base
Lock: None
Possibilities: Dawel Lugo, Jeimer Candelario

As noted earlier this month, this is a battle to watch, with Candelario and Lugo out of Minor League options. Both report to Spring Training with their timing set at the plate coming off winter ball. Here’s guessing the switch-hitting Candelario rises to the challenge.

Utility
Lock: Harold Castro
Possibility: Jordy Mercer

Harold Castro’s left-handed bat -- despite a 9-to-86 walk-to-strikeout ratio -- and his ability to play infield and outfield positions make him a near lock. The additional roster spot this season opened a chance for Mercer to provide a utility bat from the right side, along with shortstop capability in case Goodrum struggles or is injured. If Willi Castro were to win the job at shortstop, it would likely come at Mercer’s expense.

Outfield
Locks: Cameron Maybin, JaCoby Jones, Victor Reyes
Possibilities: Christin Stewart, Travis Demeritte, Jorge Bonifacio, Troy Stokes Jr., Daz Cameron

Maybin’s signing last week shored up one roster spot alongside center fielder Jones. Reyes appears set after Gardenhire’s comments last week. Stewart reported to camp in good shape and ready to compete for the primary job in left. He has a strong chance to win it, especially with Detroit’s need for left-handed hitters to balance the lineup.

Starting pitchers
Locks: Matthew Boyd, Jordan Zimmermann, Spencer Turnbull, Ivan Nova
Possibilities: Daniel Norris, Zack Godley, Tyler Alexander

Norris, coming off a productive offseason, has been throwing like he was ready for games to begin last week. With no innings limits this year, he’s nearly a lock for a starting spot at this point.

Relievers
Locks: Joe Jiménez, Buck Farmer
Possibilities: Gregory Soto, Jose Cisnero, Nick Ramirez, Bryan Garcia, Rony Garcia, John Schreiber, Matt Hall, David McKay, Alex Wilson, Zack Godley

This will be the most wide-open competition of camp. Other than closer Jiménez and set-up man Farmer, the Tigers have no one set, with a mix of young arms and serviceable veterans competing for jobs. Soto and Ramirez have a solid track to earning spots with so few lefty relievers in camp, though Alexander could slide into a role if the Tigers don’t send him to Triple-A Toledo as an insurance starter. The Tigers liked what they saw from Cisnero last year, though walks became an issue. Detroit badly missed Wilson’s veteran stability and versatility last year. If Godley makes the club, that would leave one spot for four youngsters; the Tigers would like Bryan Garcia to grab it and begin his grooming process, though that would come at Rule 5 Draft pick Rony Garcia’s expense.