Adron Chambers is one of the Cardinals fighting for a roster spot as time begins to dwindle in spring training. (Scott Rovak/USA Today Sports)

By Rob Rains

JUPITER, Fla. – The bubble burst for many college basketball teams on Selection Sunday as they saw their chance of making this year’s NCAA tournament came to an end.

With 11 games and 12 days remaining in spring training, there are eight Cardinals who know all too well what the phrase being “on the bubble” means this time of year.

At least 20 of the 25 spots on the Cardinals’ opening day roster appear locks, barring any last-minute injuries, and a couple more spots are probably safe even if spring performances probably would indicate a different result. That leaves very few spots open on the roster, with multiple players hoping they can fill those vacancies.

“We have a few questions which still need to have answers,” manager Mike Matheny said Sunday. “We’ll see what we can learn by watching. We still have roles to be defined.”

Here are the players who will be the most on-edge until they get a final decision on whether they will be in St. Louis or in the minor leagues when the season begins, listed in alphabetical order:

Matt Adams – A longshot to make the roster coming into camp, Adams has wedged himself into serious consideration by being one of the team’s most impressive hitters in camp. He is limited by the fact he can only play first base, which might force the Cardinals to make a decision about whether his value as a pinch-hitter with power – two pinch-hit home runs this spring – provides greater value to the club than carrying an extra middle infielder. It helps Adams’ cause that Matt Carpenter has played well enough at second base that the team is comfortable with him there, which could free up Daniel Descalso to be a super utility player, serving as the backup shortstop to Pete Kozma.

Ronny Cedeno – Expected to make the team when Rafael Furcal was lost for the season, Cedeno has not had a good camp. His contract is not guaranteed, which definitely leaves him in danger. With the five bench spots so valuable, will the Cardinals decide they need two backup middle infielders, Descalso and Cedeno, or has prospect Greg Garcia impressed them enough this spring to go only with Descalso (freeing up a roster spot for Adams) knowing that Garcia is only a phone call away if Kozma or Descalso is injured.

Adron Chambers – Three into one doesn’t work when configuring the Cardinals’ roster and trying to decide who will be the team’s fourth outfielder. Chambers has the versatility the team wants because of his ability to play all three spots, but so too can Justin Christian and Shane Robinson, the other candidates for this spot. The fact Chambers hits left-handed figures to work against him if Adams makes the team, as would the fact that if Adams is on the team, there is more of a probability that Allen Craig will see time in both left field and right field during the season, freeing up first base for Adams.

Justin Christian – Signed as non-roster player over the winter, Christian’s chances of making the team were improved by the fact he hits right-handed, but based on spring performances, it would be hard to justify keeping Christian after the way Robinson has played this spring. Even though the Cardinals like Christian’s veteran presence, it is hard to see a path that ends with him on the opening day roster.

Shelby Miller – He will flip-flop with Joe Kelly and get the start on Tuesday as the Cardinals try to determine who should open the season as the fifth starter. The only logical way it would appear for Miller to make the team is if he is the fifth starter. It would not make much sense for him to be the last reliever in the bullpen, pitching once a week or so for a couple of innings, when he could instead be starting, and improving, every fifth day in Memphis. The Cardinals still project Miller to be a starter long-term, and don’t want to alter that plan. Kelly, on the other hand, is expected to be on the roster, pitching out of the bullpen, even if Miller gets the nod as the fifth starter. There is still some thought in the team’s camp that his long-term role in the majors could be as a reliever.

Shane Robinson – Matheny called him the “Graperfruit League MVP” earlier this week and it would be hard to argue with that statement. Robinson has led all major-leaguers in batting average almost all spring and has been at the top of the team’s home run and RBI leaders as well. He proved last year he has the ability to come off the bench and get a hit, but it was a lack of power that concerned the Cardinals for the role he will be asked to fill. Again, if Adams is on the team, the requirements for the composition of the bench could change, and that could well work in Robinson’s favor.

Fernando Salas – Salas’ future, at least for the short time, is intertwined with the decision about who will be the fifth starter. If Miller is the starter, Kelly probably knocks Salas off the team and back to Memphis. If Kelly is the starter, Miller almost certainly will go to Memphis, freeing up the final spot in the bullpen for Salas.

Ty Wigginton – One of the two position player free agents signed by the Cardinals over the winter, Wigginton has had a horrible spring. He would be in more danger of getting released if not for the fact that he signed a two-year, $5 million contract, and it is doubtful the team would want to eat that contract without at least seeing what Wigginton can do in the regular season. In his defense, he has not been used this spring in the role he most likely will fill during the season, coming off the bench to get one at-bat late in the game.

The best guess from this vantage point is that the five bench players opening the season in St. Louis will be Tony Cruz, the backup catcher; Descalso, Adams, Robinson and Wigginton, with Kelly getting the nod as the fifth starter and Salas in the bullpen.

Around the majors

What is happening with Zack Greinke in the Dodgers’ camp is exactly why the Cardinals are having a hard time pulling the trigger on signing the Adam Wainwright contract extension. Greinke, at 29 two years younger than Wainwright, could open the season on the DL with a sore elbow after signing a six-year, $147 million contract this winter. He has pitched a total of five innings over two games this spring … As the final stretch of spring begins, Kyle Lohse is still sitting at home in Arizona, waiting for a team to make him an offer. The latest team which might need a pitcher is the Padres, who look like they will lose top prospect Casey Kelly to Tommy John surgery. The Brewers and Rangers also still seem like likely fits for Lohse, but the situation has now reached the point where he could not possibly be ready to pitch until a couple of weeks into the season. The possibility grows more likely by the day that he might not be signed until after the June draft, when teams no longer would have to worry about giving up their top draft pick, or the bonus pool money for that pick, as compensation. That would cost the Cardinals that extra draft pick, which as of now would be the 29th overall pick in the draft … St. Louisian Josh Outman, still the best name ever for a pitcher, is trying to earn a spot in the Rockies’ bullpen this spring. In five games, he has a 2.57 ERA with both of the runs he allowed coming in one appearance … Another St. Louisian, Jacob Turner, has not had a great spring and might be in danger of being sent back to Triple A by the Marlins … The conversation between a manager and a player being sent to the minors is never pleasant, but one of the more unusual ones had to be the one that occurred last week in the Giants’ camp, where manager Bruce Bochy had to tell his son Brett, a pitcher, that he was being sent out. He actually did it while they were eating dinner. “He was disappointed I didn’t bring him in to cut him,” said Bruce Bochy, the manager. ”I may do it tomorrow just to make him feel better” … One of the bigger questions entering spring training was whether Aroldis Chapman would be a starter or the closer for the Reds, and the answer is still unknown. Chapman says he prefers to close, which could make it an awkward moment if the team decides he will be a starter.