CHICAGO -- The Cubs know that their late-inning setup situation will evolve in the upcoming campaign, even though Craig Kimbrel regained the trust of manager David Ross as Chicago's closer last season.

On Thursday, the Cubs added another late-inning option to the mix, agreeing to a one-year contract with free-agent reliever Brandon Workman,. The deal, first reported on Wednesday and was pending a physical, includes a $1 million base salary with another $2 million possible via incentives, according to a source. The Cubs designated infielder Sergio Alcántara for assignment in a corresponding move.

"The bullpen's going to have to be fluid," president of baseball operations Jed Hoyer said in a Zoom call on Tuesday. "Guys are going to have to step up and step into different roles."

The Cubs also reached an agreement on Wednesday with right-hander Pedro Strop on a Minor League deal that includes an invitation to Spring Training, per a source. Strop was a long-time staple as Chicago's eighth-inning arm and will now be in camp competing for a spot in the 2021 bullpen.

Workman is coming off a tough showing in 2020 (5.95 ERA in 21 games in stints with the Red Sox and Phillies), but the righty was dominant in his last full season. In '19, the righty turned in a 1.88 ERA with 104 strikeouts against 45 walks in 71 2/3 innings for Boston.

That 2019 performance makes Workman a leading candidate to step up as an eighth-inning option ahead of Kimbrel. For his career, Workman has logged a 3.89 ERA in 209 games, posting nearly identical splits against righties (.235 average and .688 OPS) and lefties (.237 average and .714 OPS).

Last year, the Cubs unearthed a gem in righty Jeremy Jeffress, who was coming off a down season in 2019. He emerged as a part-time closer in '20, allowing Kimbrel time to sort through some early issues, and finished with a 1.54 ERA in 22 appearances.

Jeffress remains unsigned as a free agent and Chicago's other primary part-time closer and setup man, Rowan Wick, is currently dealing with an intercostal setback, per Hoyer. So as the Cubs' pitchers and catchers began workouts on Wednesday in Arizona, the late-inning picture is fuzzy.

"As long as Craig is who we know he can be, he's going to be our closer," Ross said on Tuesday. "But I do think there's so many guys in that bullpen that are going to help to our success. Craig's a big part of that on the back end. But there's a lot to deal with, as far as how long a season goes."

This offseason, the Cubs also signed lefty Andrew Chafin and righties Kohl Stewart and Jonathan Holder to MLB deals. Lefty Kyle Ryan and righty Dan Winkler inked deals to avoid arbitration. Chicago also selected righty Gray Fenter in the Rule 5 Draft and claimed righty Robert Stock off waivers.

And then there are the Cubs' internal holdovers -- arms such as Jason Adam, Duane Underwood Jr., James Norwood and Dillon Maples, among others. Adam, in particular, impressed the Cubs down the stretch in 2020. Underwood and Maples are out of Minor League options.

Among the non-roster bullpen candidates, there are some veterans (Adam Morgan and Strop, for example) and younger possibilities (Trevor Megill and Brendon Little, for instance).

Strop spent time at the Cubs' alternate training site to end 2020, following his release by the Reds after a four-game, injury-marred stint in their bullpen. Chicago at least knows what it has in the 35-year-old Strop, who not only was influential in the clubhouse, but a steady late-inning performer (2.90 ERA in 411 games for the Cubs from 2013-19).

The bullpen puzzle is something the Cubs will be piecing together all spring.

"It's rare that you know exactly what the roles are going to be going into Spring Training," Hoyer said. "I think we were a little bit spoiled by a guy like Stropy, for example, as sort of the eighth-inning guy for a number of years. That's not normal.

"I like the arms we have down there. And I like our infrastructure's ability to get the most out of those guys. So, yeah, I think Rossy will have a lot of options. But exactly how it's going to sort out [before] the closer, I think, will be the question."