As Cubs manager David Ross continues to plot out his Opening Day bullpen, he believes the club has the arms in place to help withstand the inevitable ups and downs of the coming campaign.

"We've got some sneaky good pitchers that maybe are not on the radar," Ross said on Friday. "I'm seeing more depth than I thought we had."

On Friday, the Cubs optioned left-hander Kyle Ryan and James Norwood to Triple-A Iowa, among a handful of other roster reductions. Those decisions continued to bring Chicago's Opening Day relief corps (eight or nine arms) into focus.

Here is the latest breakdown of how the Cubs' bullpen is shaping up:

The virtual locks: Andrew Chafin, Craig Kimbrel, Ryan Tepera, Dan Winkler, Brandon Workman
These five arms are under Major League contracts and bring the most big league experience to the table. Ross values the latter when it comes to the high-leverage roles, and there is little doubt that this will be Chicago's primary late-inning cast for Opening Day.

Kimbrel was dominant in September last year, and Ross has made it crystal clear that the veteran reliever is the closer. The setup situation is more fluid, though Workman looks like a leading contender for the main job. Expect Ross to mix and match ahead of Kimbrel as he gets a feel for the best combination.

Righty Rowan Wick would have fit in this category, but he will open the season on the injured list due to an intercostal injury.

Earning trust: Jason Adam
While Wick was out down the stretch last year, Adam earned more opportunities to show what he could do in leverage spots. The righty posted a 1.80 ERA with 12 strikeouts in 10 innings in September, featuring elite spin numbers. Only Trevor Bauer and Lucas Sims had a higher average four-seam rpm than Adam (2,728) in 2020 (minimum 100 pitches).

"I would say Jason proved himself last year," Ross said. "And he put a lot of work in this offseason to be a guy that is highly considered to have a spot in the bullpen, for sure."

The wild card: Dillon Maples
Maples nearly had an immaculate inning (three strikeouts on nine pitches) on Thursday, but then hit Cleveland's Bradley Zimmer with a pitch. Things escalated momentarily, but the Cubs righty got back on track with a swinging strikeout of Bobby Bradley, who whiffed on a slider that actually hit the batter's leg.

"His slider is a wipeout pitch," Cubs starter Jake Arrieta said via Zoom on Thursday. "Any time you can throw a breaking ball that hits a guy, and they still swing at it, you know you've got pretty good stuff."

The stuff has never been the issue. Maples features a slider with a spin rate that routinely tops the elite 3,000 rpm threshold. His fastball flirts with triple digits. But while Maples has 39 strikeouts in 23 1/3 MLB innings (2017-20), he has also walked 25 and logged an 8.49 ERA.

This spring, Maples (out of Minor League options) arrived with a refined delivery -- shortening up his arm stroke -- and his strike throwing has improved. Through five Cactus League outings, the righty has nine strikeouts and no walks, but he has still allowed seven runs (four earned).

"Good stuff is great, but outs are what matter," Ross said. "I think Dillon's in a really good place mentally and physically, and he's got a real shot to make our team."

Swing men: Adbert Alzolay, Alec Mills, Shelby Miller (non-roster)
One or two from this group could be in the bullpen as a multi-inning arm come Opening Day. This trio is in the hunt for the lone vacancy in the rotation, but the Cubs also plan on having flexibility at the back of the starting staff to help manage innings. Translation: The arm (or arms) that are in the bullpen come April 1 will also be making starts as the season progresses.

Mills will have a home on the staff in some capacity. Chicago is waiting to learn if Alzolay has a Minor League option for 2021, which could impact where he starts the year. Miller did not pitch in '20 (elected not to play), but he has been impressive this spring.

"Shelby's done a phenomenal job, coming in here and opening some eyes," Ross said. "I've liked the poise. I've liked the pitch execution for the most part. I've liked the way he's gone about his business."

Second lefty: Rex Brothers (non-roster) or Brad Wieck
Ryan has been a fixture in the Cubs' bullpen for the past two seasons, but the lefty was delayed at the start of camp due to a stay on MLB's COVID-19 related injured list. The lefty has built up to facing hitters again, but needs more time to get ready for the long season.

"We've put together a plan for Kyle," said Ross, who noted that part of the lefty's value is in being able to handle multi-inning outings.

With all the camp reductions that have happened to date, Brothers and Wieck remain as the lefty options beyond Chafin for the Opening Day bullpen.

"If we go with a second lefty," Ross said, "those two guys are in the mix, for sure."

Rest of the field: Jonathan Holder, Trevor Megill (non-roster), Pedro Strop (non-roster)
Holder has a Minor League option, while neither Megill nor Strop are on the roster. Those considerations put them on the Opening Day bubble, as maintaining depth is important at the start of a season. Of the three, Megill has been the most impressive this spring, flashing an upper-90s fastball and showing good command through six Cactus League outings (1.69 ERA, seven strikeouts and one walk in 5 1/3 innings).