MESA, Ariz. — The Cubs’ starting rotation is mapped out for the opening series of the season against the Milwaukee Brewers at Wrigley Field:

Thursday — Kyle Hendricks vs. Corbin Burnes
Friday — Justin Steele vs. Brandon Woodruff
Saturday — Marcus Stroman vs. Freddy Peralta
Sunday — Drew Smyly vs. TBD

Many assumed all along that Stroman would get the ball for Game 2 behind Hendricks. David Ross wouldn’t elaborate on the reasoning behind the order but it makes sense for a couple of reasons: Slotting Steele in between Hendricks and Stroman staggers the righties and it also spaces out the two pitchers capable of carrying a heavy workload.

Hendricks and Stroman have been built up more than any other pitcher in Cubs camp, with Hendricks throwing about 75 pitches on Saturday and Stroman reaching 85 pitches in a simulated game Sunday.

The Cubs are hoping they wouldn’t need the bullpen to cover as many innings in the games Hendricks and Stroman pitches, allowing them to space out the rest. That’s especially helpful since many relievers are not yet ready for outings on back-to-back days after a shortened Spring Training.

It also makes sense to go righty-lefty-righty-lefty through the first four games to differentiate looks for the opposing hitters.

The Cubs won’t technically need a fifth starter until the ninth game of the year on April 16. When they do, Alec Mills or Keegan Thompson could get the call but in the opening series of the season, both right-handers should be available as multi-inning options out of the bullpen.

Opening Day roster coming into focus

Just before Monday’s game, the Cubs cut the spring roster down to 31 players.

Infielder Ildemaro Vargas and pitchers Jonathan Holder, Robert Gsellman, Steven Brault and Stephen Gonsalves were assigned to Triple-A Iowa. All five players were in camp as non-roster invitees.

And during the game, the team let young reliever Ethan Roberts know he would be on the Opening Day roster. 

This is the moment Ethan Roberts found out he made the opening day roster. @EthanXXVI @WatchMarquee @Cubs pic.twitter.com/78fGenu9ZD

— Elise Menaker (@EliseMenaker) April 4, 2022

Roberts worked a shutout inning against the White Sox and ended the frame by knocking down a comebacker with his bare hand. When he got back to the dugout, everybody was asking how his hand was and he insisted he was fine.

“Everybody’s like, ‘good job, how’s your hand?'” Roberts said. “And guys start looking at me weird and I’m like, what is going on? Rossy comes up and he’s like, ‘hey can you still shake my hand?’ And I’m like, ‘yeah my hand’s good. I promise.’ And he’s like, ‘good, you just made the team.’ And I just melted.

“Of course for everybody, it’s just life-changing for me. This is insane. Just a loss for words. It’s hard to put it in words. It’s something I’ve been dreaming about for a long time.”

Roberts is from Sparta, Tenn., and his hometown has a little sign at the entrance that says it is the home of Lester Flatt, a bluegrass singer. 

“I said, ‘Dad, that’s gonna say home of Ethan Roberts one day.’ That was when I was 12,” he said. “So I’ve been thinking about this for a long time. I would kill for this game, to keep playing this game as long as I can. I want to coach later. I’m always going to be in the game. It’s been probably since before I was 12, I’ve been thinking about this moment and it’s here.”

Roberts, 24, is an exciting up-and-coming relief prospect who has not yet pitched in the big leagues. He was a 4th round pick in 2018 and posted really good numbers in the minor leagues last season (4-2, 3.00 ERA, 0.96 WHIP, 12.0 K/9).

This spring, he hasn’t allowed a run in 5.1 innings while striking out 7 batters against only 1 walk.

“He’s been really good,” Ross said before Monday’s game. “His numbers speak for themselves. The way he’s come out, the velocity has just continued to stay at a high level, the wipeout slider, the strikeouts, throwing strikes. All those things are real positive from a young guy.

“He’s really made an impression on me and the coaching staff this spring training.”

The Cubs will still have to make three more moves to get down to 28 by Thursday’s Opening Day. At least one of those moves will be Wade Miley, who is currently rehabbing an elbow injury.

Andrelton Simmons is likely to be another move, as the veteran shortstop has been slowed in camp with a shoulder issue. He took part in the Cubs’ defensive drills Monday but did not throw during the practice.

Even if Simmons is unable to join the team for Opening Day, the Cubs are hopeful it won’t be long before he’s in Chicago.

“He feels good; we feel good about it,” Ross said. “Each day has gotten better and he comes in with better feedback every single day. Barring some setback, we feel there’s a good possibility it’s short.”

Assuming Simmons starts the year on the IL, the final couple of roster spots will come down to what the Cubs’ priorities will be in the first series of the season.

They could opt for another hitter in Alfonso Rivas, who provides depth at first base and another left-handed bat to play matchups. He has minor league options remaining so the Cubs could send him down to Triple-A later in the year if the need arises.

[MORE: From unheralded prospect to the majors, Scott Effross offers Cubs ‘unique look’ out of bullpen]

The other option is going with another bullpen arm. With Roberts already on the roster, Michael Rucker is another reliever vying for the last spot or two on the staff.

Rucker, 27, was in Chicago last year and is stretched out to go multiple innings, which could be an added benefit for the early-season bullpen. He has pitched well this spring with a 2.25 ERA, 0.88 WHIP and 11 strikeouts in 8 innings.

“He’s continued to grow,” Ross said. “His stuff is major league quality stuff. I think consistency is still one of the issues for him and being able to know what we’re getting every time out. He’s shown good signs of that.”