GOODYEAR, Ariz. -- As the Reds keep an eye on Alex Wood’s sore lower back, they are thinking about alternatives should their left-handed starter not be ready to begin the season.

Right-hander Tyler Mahle appears to be the leading candidate to replace Wood. In two spring games, including one start, Mahle has three scoreless innings with three hits, two walks and six strikeouts. Originally scheduled for Monday, Mahle is now pitching in Tuesday’s split-squad game against the Cubs.

“I think Tyler is part of that discussion, for sure. It has not been determined, and Alex’s readiness for the season hasn’t been determined, but we do need to start planning for multiple scenarios,” Reds manager David Bell said. “Tyler is right there anyway. He’s doing everything he can. He’s going to be an option certainly for helping us, whether it’s the beginning of the season or shortly thereafter. He’s definitely part of that picture.”

Bell did not identify other potential candidates.

Mahle, 24, hasn’t pitched in a Cactus League game since March 1 vs. the Giants, but last pitched in a two-inning simulated game last week.

As a rookie last year, Mahle endured inconsistency as he went 7-9 with a 4.98 ERA in 23 starts and 112 innings. From the start of the 2019 camp, Bell noted that Mahle, who wasn’t named in the five-man rotation, would be prepared to be used as a starter -- either for the big leagues or Louisville. Mahle knew the additions of Wood, Tanner Roark and Sonny Gray meant he had to raise his game even more.

“As the team gets better, I think everybody plays a little better,” Mahle said. “It’s fun knowing you can be on a staff that got so much better during the offseason. This whole team got better.”

According to Statcast, Mahle relied heavily on his four-seam fastball, throwing it nearly 68 percent of the time. He threw only 10 curveballs all season, while his slider and changeup were often ineffective.

The lesson Mahle learned was that his secondary pitches needed to be better. He couldn’t live on his fastball the way he did in the Minors.

“Guys started canceling stuff out,” Mahle said. ‘He’s not going to throw the changeup in the strike zone, so I won’t look for it. Same with the slider.’ I saw that, so it would be nice to go out and pitch and make people have to respect that I can throw the other stuff for a strike. That makes my fastball play better.”

Working with pitching coach Derek Johnson, Mahle has ditched the changeup and slider and will stay with the four-seamer, a curveball and a hybrid split-finger/changeup pitch.

Mahle also quietly dealt with a sore shoulder for a good part of 2018, which was something he concealed. He was eventually shut down after one September outing with a stress reaction in his rotator cuff.

“In the Minors, I never got hurt, but any time something was bothering me, I would take care of it on my own. That’s the way it is,” Mahle said. “You want to stay on the field. I definitely learned that in the big leagues, it’s a different story. To stay on the field, you need to say something. Those guys are going to help you.”

Garrett in glasses

Reds lefty reliever Amir Garrett has been wearing glasses in the clubhouse and away from the complex all spring. He’s never needed them until now.

“My eyes aren’t that bad, but I can definitely tell the difference when I have them on,” Garrett said. “I’ve got contacts and glasses. The contacts, I wear for the game. The glasses I wear off the field.”

First roster moves

The Reds made their first Spring Training roster moves as outfielder Jose Siri and right-handed pitchers Jackson Stephens, Keury Mella, Jimmy Herget, Alex Powers and Felix Jorge were reassigned to the Minor League camp. That brings the camp roster down to 57 players.

There were no surprises among the group that was sent out, although Stephens has the most experience with 36 big league games, including 29 last season. He posted a 6.00 ERA in five games this spring, with four earned runs and eight hits over his six innings.

“He’s showed us some really good things,” Bell said. “I feel like I got a good look at him. He’s showed the ability to make adjustments. He’s right on the brink. It’s just a matter of the opportunity is not there right now, but he’s so close. I was just encouraging him to keep going and do what he’s doing.”

Up next:

In a pair of split-squad games, the Reds will face the Padres at 9:05 p.m. ET in Goodyear, and the Cubs at 10:05 p.m. in Mesa. Luis Castillo will make the start vs. San Diego, while Mahle takes on Chicago.