MESA, Ariz. -- The Cubs have pieced together a starting rotation that is built around pitching to weak contact and relying on sound defense. That makes having some swing-and-miss arms imperative for the bullpen.

Last season, Ryan Tepera provided precisely that for the Cubs, who have now reached an agreement with the right-hander to return on a Major League deal, the club announced Tuesday. Right-handed pitcher Duane Underwood Jr. was designated for assignment to open a roster spot.

"We talk about similarities of some of our starters," Cubs pitching coach Tommy Hottovy said last week. "That also makes our bullpen look so much different. When our bullpen's coming in after that, with just different stuff."

The 33-year-old Tepera posted a 3.92 ERA in 21 appearances last season, piling up 31 strikeouts against 12 walks in 20 2/3 innings. His 34.8 percent strikeout rate ranked 19th among qualified MLB relievers, and his cutter had a 62.2 whiff percentage, according to Statcast.

The addition of Tepera will lengthen out a bullpen that has a couple of jobs for the taking this spring.

Craig Kimbrel is installed as Chicago's closer, with righty Brandon Workman and lefty Andrew Chafin in the mix as setup options. The Cubs also retained righty Dan Winkler over the winter, while bringing righties Kohl Stewart and Jonathan Holder into the fold on MLB deals.

The Cubs are also trying to find the best way to approach the rotation in the coming season, knowing that more than five starters will be required. That could lead to a situation where pitchers like Alec Mills and Adbert Alzolay wind up in relief roles at times. Stewart could also fit into that swing-man category.

Other relief candidates this spring include Jason Adam, Gray Fenter, Dillon Maples, James Norwood, Robert Stock, Duane Underwood Jr. and Brad Wieck, among others, including some non-roster invitees. Rowan Wick (intercostal injury) and Kyle Ryan (on MLB's COVID-19 related injured list) are sidelined at the moment.

While Cubs manager David Ross would not discuss the pending signing of Tepera, he did speak to the righty's importance to the bullpen last season.

"Ryan Tepera, last year, did a really good job for us of coming in and pitching some really big innings," Ross said on Friday. "I thought he bridged the gap to the back-end really well. That sixth, seventh spot where maybe Row Wick was used the day before. There's so many pieces to that bullpen down there. He was a significant piece for us last year that kind of came in and got us out of big spots. He was able to handle the moment."