JUPITER, Fla. -- With a series of roster moves made Friday morning, the Cardinals inched closer to finalizing their Opening Day roster.

Among those earning spots on it were catcher Matt Wieters, who will back up Yadier Molina, and power-hitting outfielder Tyler O'Neill. Reliever Mike Mayers has also been named to his first Opening Day roster in a decision that nudged lefty Chasen Shreve off.

The Cards designated Shreve for assignment and plan to fill their seventh (and final) bullpen slot closer to Opening Day on Thursday. Right-hander John Brebbia and lefty Tyler Webb stand as the leading candidates to claim it.

The addition of Wieters also leaves Francisco Pena in limbo with only two days remaining before St. Louis departs Florida. He will remain a non-roster invitee in camp, but he can request his release to take a job elsewhere if he doesn’t want to report to Triple-A Memphis.

Pena's agent will spend the next few days gathering intel on whether another club is interested in the 29-year-old catcher.

Pena arrived in camp earmarked to be Molina’s backup for a second straight season, but he found unexpected competition in Wieters, who signed a Minor League deal with the club on February 27. Wieters went 3-for-24 with one extra-base hit and nine strikeouts after getting a late start in Grapefruit League play. His inclusion on the roster gives the Cardinals an experienced second catcher and a switch-hitter off the bench.

“He came in, did a nice job," manager Mike Shildt said. "[We're] excited to have him, excited to have his experience, his presence and his ability. He’s taken good at-bats this spring. He looks healthy. He’s feeling good. He’s fit in seamlessly. He’s a real pro. He’s been a nice addition to the clubhouse.”

Wieters joins a bench that will also include O’Neill, who has blasted a team-high five home runs in a team-high 55 spring at-bats. Eight of his 10 total hits have gone for extra bases.

“Tyler had to come and earn it,” Shildt said. “Spring Training is about getting ready for the season. It’s also showing what you can do, and Tyler has more than demonstrated that he has the skill set to help us win games and earn a spot.”

O'Neill and Jose Martinez will serve as extra outfielders for the Cards. O’Neill brings the versatility to play all three outfield positions.

Three candidates -- Jedd Gyorko, Yairo Muñoz and Drew Robinson -- remain for the final two bench jobs. Gyorko’s health is still a question mark, as he hasn’t appeared in a Grapefruit League game since March 3 due to a right calf injury. He was scheduled to take a few at-bats in a Minor League setting on Friday and will continue to work on the back fields early next week. Gyorko has been cleared for moderate-intensity running.

By Wednesday, the Cardinals will have to decide if Gyorko is ready to begin the year on the active roster.

“We want him to be able to be ready to play a full game and do all the things that he would expect to do in a full season and not feel compromised at the moment and not be compromised moving forward,” Shildt said. “It’ll be a constant evaluation.”

If Gyorko were to start the season on the injured list, both Munoz and Robinson would open the year with the big league team.

The other roster unknown is in the bullpen. Mayers has been told that he will begin the year in St. Louis' bullpen, along with Andrew Miller, Jordan Hicks, Dominic Leone, Alex Reyes and John Gant. If the Cardinals were to carry Brebbia, as well, that would leave Shildt only one lefty (Miller) in his bullpen.

Shreve had been projected to be another, but his so-so spring left him on the outside. He was scored upon in four of his eight outings and allowed two runs on two hits and two walks in his most recent appearance on Thursday.

The Cards can try to trade Shreve or place him on waivers within the next week. If he were to clear waivers, Shreve -- who joined the club as a midseason acquisition last year -- could be outrighted to Triple-A. The more likely scenario is that he’ll be claimed by another team.

“Chasen has done everything we’ve asked him to,” Shildt said. “He’s fit in wonderfully. It came down to, really, the fact that we’re carrying seven in our bullpen.”

Worth noting

• The Cardinals have four players who are confirmed to be starting on the 10-day injured list: right-hander Carlos Martinez, righty Luke Gregerson, left-hander Brett Cecil and outfielder Justin Williams.

• The club has not determined whether Matt Carpenter (back tightness) will appear in another Grapefruit League game. If he does, it won’t be until Sunday. Carpenter’s last appearance came on March 15.

Up next

Miles Mikolas will make a final tuneup before his Opening Day start when he faces the Nationals in a 12:05 p.m. CT game on Saturday. Mikolas is expected to throw the first four innings, and Dakota Hudson will then carry the game to its conclusion. The outing will be Hudson’s first since being named the team’s fifth starter.