By Bruce Levine–

MESA, Ariz. (CBS) — The Cubs are ready to begin their title defense with a 25-man roster that is comprised of 13 position players and 12 pitchers.

That composition comes after Wednesday’s news that left-handed reliever Brian Duensing will open the new season on the disabled list with a back issue. That means both outfielder Matt Szczur and infielder Tommy La Stella are in line to break camp with the Cubs.

“The way we are very likely will be the way to break camp, with Matt Sczcur and Tommy LaStella on the club,” president of baseball operations Theo Epstein said Thursday. “Brian Duensing, who had those back spasms, is still a little bit behind. He will start the year on the DL. We will start the year with a seven- man bullpen.”

Szczur is out of minor league options and would be lost if he went on waivers. The market for him has been real but not flush with the type of player the Cubs would like back in return. The team desires a left-handed relief pitcher or an infielder who can play everywhere are desired by the Cubs with the vision of solidifying backup roles at Triple-A Iowa.

Going with the 12-man pitching unit was made easier by the Cubs having five off days in April after they open the season against the Cardinals in St. Louis on Sunday night.

“A seven-man pen certainly with off days should be fine,” Epstein said. “With us having early off days, we should be OK. We can let (Duensing) fully recover from the back spasms.”

The Cubs will have an abundance of quality outfielders early on with this roster. Eventually, the bullpen will end up with eight men in it periodically throughout the season.

“This will be a normal baseball season with lots of roster rooms throughout the season,” Epstein said. “Some guys get nicked up, and we make adjustments along the way. I know there is always a ton of emphasis on the Opening Day 25-man roster. It really is just one day out of 183. There will be a lot of transactions.”

Szczur was happy to stay with the Cubs for now, though in the long run, he would like to be a starter somewhere. He’ll be a backup to Kyle Schwarber in left field, Jason Heyward in right field and the platoon of Albert Almora and Jon Jay in center.

Szczur hit .259 with a .712 OPS in 107 games last season.

“I am excited to still be with the ball club,” Szczur said. “It will fun to be there and get out rings while wearing those gold jerseys. It should be an interesting year and great year as well.”

Manager Joe Maddon loves the makeup of his new group.

“You of course start with 25,” Maddon said. “It never ends up looking like that. This has been a great spring training — 25 men leave with you. In reality, it takes more than that.”

Bruce Levine covers the Cubs and White Sox for 670 The Score and Follow him on Twitter @MLBBruceLevine.

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