FORT MYERS, Fla. – The Twins’ quickly thinning bullpen depth took another hit on Sunday, when president of baseball operations Derek Falvey announced that reliever Justin Topa will begin the season on the IL with left knee tendinitis.

That makes three members of the projected leverage core at the back end of the bullpen — Jhoan Duran, Caleb Thielbar and Topa — who will open the season on the shelf, all of a sudden very fortuitous that the Twins bolstered their bullpen depth as much as they did over the course of this offseason.

Here’s what to know about how this could impact the Minnesota bullpen and roster plans.

How bad are the injuries?

Topa (left knee tendinitis) actually wanted to pitch through the soreness, Falvey said, which he sustained when he jammed his foot a bit while backing up home plate, but the Twins chose to get out ahead of things. They’re giving him roughly a week off his feet before building him back up according to how he feels.

“We don’t want tendinitis to track through the year if we can knock it out ahead of time, so we’re going to knock it out now,” Falvey said.

Duran (right oblique strain) needs to wait until he has no more symptoms before he can start ramping back up, and oblique injuries are typically treated with an abundance of caution because of how they can flare up and linger at times. He was shut down on March 16 when it flared up ahead of a live batting practice.

Thielbar (left hamstring strain) threw a bullpen on Sunday and is said to already be moving better and responding with better strength, according to Falvey. He had also maintained his bullpen progression throughout the spring, so it doesn’t seem as though he’ll be too behind.

What does the leverage corps look like?

Griffin Jax and Brock Stewart will get the highest-leverage situations — it’s unclear which will be given the ninth inning, or if the Twins will even have a consistent “closer” in Duran’s absence — and the bridge roles will go to Jay Jackson and Steven Okert, both offseason acquisitions, due to their relative seniority and their greater exposure to such situations.

“We’re going to have to answer some questions that we haven’t had to answer in a while,” manager Rocco Baldelli said. “It’s going to be getting through one inning at a time and then getting the next best option out there to get the next three outs. … We’re going to have to find some new ways to answer the same questions.”

How does this impact roster decisions?

This seems to consolidate a spot on the roster for young left-hander Kody Funderburk, who got a cup of coffee in the big leagues down the stretch last season and is well-regarded in the organization coming off a 2.36 ERA in the Minors last season and an 0.75 ERA in 11 MLB appearances with a fantastic 19 strikeouts and five walks in 12 innings.

Jorge Alcala’s stuff has played up this spring, with his fastball again playing in the 96-98 mph range in the Twins’ 8-3 loss to the Orioles on Sunday, and despite some inconsistency in his results, he seems to be in better position for the roster due to all this attrition.

After that, really, the only other two pitchers remaining on the 40-man roster for the final two bullpen spots are Josh Staumont and long relief option Cole Sands, with Daniel Duarte standing out most prominently among the Twins’ non-roster options — barring any external additions, of course. Staumont’s velocity is back up following a bout of food poisoning, though his control numbers have been shaky this spring.

The Twins were hoping to get Duarte more in the strike zone with some adjustments this spring, and that’s largely been successful, as the control-challenged right-hander has dealt 11 strikeouts without a walk. But due to some roster considerations, it’s sometimes advantageous for a team to keep an NRI-type pitcher in Triple-A instead of breaking camp with that player.

Are the Twins looking outside the organization?

This is always a busy time of year for monitoring the waiver wire and players who are becoming available around the league due to the cascade of contract stipulations and cuts that trigger as camps get trimmed down — and Falvey said the Twins simply remain in a monitoring stage, given they’re happy with some in-house non-roster options.

“I would say that we are monitoring the opt-outs and guys who are around and available, and having conversations with different people,” Falvey said. “More just as we continue to build up depth, we have guys in camp who we think can do some of this, certainly fill some of these roles. It never hurts when you’re down a few to keep an eye on how to add to that depth.”