LAKE BUENA VISTA, Fla. -- Assuming all felt fine during his game of catch on Monday, Chris Carpenter is tentatively scheduled to return to the mound on Wednesday to again throw batting practice. Carpenter threw a 40-pitch batting practice session on Sunday, marking the first time he had faced hitters since March 3.

While the Cardinals remain loose with Carpenter's schedule, manager Mike Matheny said it would still be premature to rule the right-hander out for an Opening Day start. With that April 4 game now 16 days away, Carpenter would have to make his first Grapefruit League appearance no later than March 25 if St. Louis wants him to make two spring starts before Opening Day.

"I just think we've been very intentional in saying that we just don't know," Matheny said. "It's kind of been that way from the beginning. We'll see how it looks on Wednesday. As of right now, we're going to leave it in limbo."

The Cardinals still intend to leave a lot of these decisions up to the 36-year-old Carpenter, who has said he isn't sure how many game appearances he would need before starting the season. Even before the neck stiffness became an issue, Carpenter was expected to cut back on his innings this spring because of the workload he shouldered in 2011. That's why the club remains open to the possibility that Carpenter could be ready to go after only two spring outings.

While Carpenter's plans remain in limbo, Lance Lynn continues his preparation to be a starter in case Carpenter is not ready. And somewhat surprisingly, given how recently Lynn was thrust into a starting role, he became the first Cardinals pitcher to finish five innings this spring.

Lynn did so on Monday, needing only 60 pitches in the five-inning effort. He retired the first 12 hitters he faced before allowing two singles, a walk and a run in the fifth. Lynn pointed to some troubles pitching out of the stretch as the reason that inning got a bit out of hand.

"It was one of those things where I was trying to do too much," said Lynn, who hadn't been scored upon in his previous two outings. "Once I got into the stretch, I got to where I was trying to manipulate the ball too much instead of just pitching how I was in the first couple of innings."

Schumaker has oblique tear; DL stint likely

LAKE BUENA VISTA, Fla. -- The Cardinals appear likely to open the season without Skip Schumaker, who had his oblique injury diagnosed as a tear by an MRI exam on Monday.

Schumaker sustained the right oblique injury during an at-bat on Friday, but it wasn't until Monday that the Cardinals received a more firm diagnosis on the severity. An oblique tear can also be characterized as a strain, and it is the same injury that Schumaker suffered during the postseason last year. He missed the National League Championship Series as a result.

The club does not currently have a timetable for Schumaker's return to baseball activities, but oblique strains can linger. The timetables for such injuries also widely differ from case to case.

Spring Training
• Spring Training schedule

With Schumaker sidelined indefinitely, the Cardinals' second base competition becomes a two-man battle between Tyler Greene and Daniel Descalso. How Schumaker might fit back into that mix will be determined both by how he fares when he returns and what type of production the Cardinals are already getting at the position.

Assuming Schumaker begins the year on the disabled list, the Cardinals will also have another bench spot to fill. The club will have to keep at least one extra outfielder and likely even put a second on the 25-man roster until Allen Craig returns. Craig, who is recovering from right knee surgery, is also set to begin the year on the DL.

Schumaker has been on the DL only one other time in his career, that coming last spring when he hyperextended his right elbow.

DH confusion forces Lynn into batter's box

LAKE BUENA VISTA, Fla. -- Lance Lynn had no intention of going anywhere but to the mound on Monday. Those plans changed, though, when he showed up at the Braves' ESPN Wide World of Sports complex and found out that for the first time this spring he'd also have to hit.

Manager Mike Matheny said that he was under the impression that per an agreement clubs made prior to the start of Spring Training, National League teams would be able to utilize a designated hitter until Thursday. Matheny had every intention of doing so, too, until he was informed that the Braves wanted to bat their pitcher.

Matheny was then told that if the two clubs couldn't agree on the use of the DH, then NL regular-season rules would apply. That meant that instead of having Bryan Anderson serve as the DH and hit in the ninth spot in the order, Lynn would have to bat.

Entirely unprepared, Lynn borrowed Tony Cruz's batting helmet, which, as Lynn described it, was about two sizes too small. The bat Lynn took to the plate belonged to Eugenio Velez, though Lynn never put it to use. He struck out looking twice and never swung.

Though Lynn did come out for batting practice on Monday, he had taken very few swings previously this spring.

"I wasn't in the hitters' group at the early part of camp like some guys," said Lynn, who allowed just one run on two hits over five innings. "I've had a little bit less than everyone else. It worked out well. I was able to track some balls, and maybe I'll be ready to go next time."

Worth noting

• Reliever Fernando Salas rejoined the Cardinals on Monday after going home to Mexico for the birth of his son. Salas, who hadn't pitched since March 12, converted a save opportunity in Monday's appearance even after getting into some trouble in the bottom of the ninth. He allowed one run, and the Braves loaded the bases with one out before Salas ended the threat with two flyouts.

• Outfielder Carlos Beltran connected for his first home run of Spring Training on Monday. All of Beltran's five spring hits had been singles before he went deep off Atlanta's Julio Teheran in the sixth.

"You want to feel good at the plate," said Beltran, who started in right field. "I know that will come. The most important thing for me is just for my body to feel good. Right now, I feel good. I'm able to do everything that I'm supposed to. I feel like every day I'm improving. That's the most important part."

• Though manager Mike Matheny had Ryan Jackson start Monday's game at second, the Cardinals' plans are to make Jackson the everyday shortstop in Triple-A Memphis this season. That means that the organization will have former first-round pick Pete Kozma, who has played primarily at short in the Minors, move around to other spots in the infield. He'll likely log regular time at second base.

• Matheny, the coaching staff and several players will spend the night in the Orlando area on Monday since Tuesday's game is in nearby Kissimmee, Fla. Players scheduled to appear in only one of the two games are busing up from Jupiter, Fla., just for the day.

• The Cardinals will trim their camp numbers again on Tuesday, following the team's game against the Astros. The club's Spring Training roster currently has 44 players.