Is the Cardinals' window finally closing?

A man who spent just one season wearing a St. Louis Cardinals uniform may have inadvertently provided the talking point for what could be a pivotal junction in this team's long and, quite frequently, glorious history.

Jason Heyward, trying to explain why he bolted to the rival Chicago Cubs, hinted that he -- and, no doubt, his agent and advisors -- wondered whether the Cardinals' window might be closing, at long last. For a generation of Cardinals fans raised on October excitement, that raises the most frightening of notions.

Now, like it or not, this season becomes about proving Heyward wrong or proving Heyward right, with hints beginning to trickle in as soon as this week. Pitchers, catchers and recuperating players report on Wednesday to the team's training camp in Jupiter, Florida.

Does the team's aging core -- ostensibly, Adam Wainwright, Yadier Molina and Matt Holliday -- have another run or two in it to bridge a gap in the farm system? Are the team's young players better than Heyward thinks they are? Or, after five straight playoff appearances and two World Series titles in the past decade, are the Cardinals headed for a rare fallow period in their history?

If you want to worry a middle-aged or older Cardinals fan, just mention the 1970s, when an aging Lou Brock was the only motivation for many fans to visit old Busch Stadium.

Like it or not, Heyward simply voiced, in refreshingly candid terms, what some worried Cardinals fans were already thinking.

"You have Yadier, who is going to be done in two years maybe. You have Matt Holliday, who is probably going to be done soon. … Guys like that are what really introduced me to the St. Louis Cardinals organization," Heyward said. "I felt like if I was to look up in three years and see a completely different team, that would kind of be difficult."

Heyward's suggestion is not an outrageous leap. Eras change in baseball and it's hard to stay on top indefinitely. It happened to the Philadelphia Phillies and, to a lesser degree, the New York Yankees. Wainwright, 34, Molina, 33, and Holliday, 36, all have been prone to long-term injuries these past few seasons. Their production won't remain steady forever.

Many people believe the team's farm system, in part because it has graduated so many players to the major leagues, is dangerously thin at the top. What seemed to rankle Cardinals manager Mike Matheny about Heyward's comments was the suggestion the team's winning culture is in jeopardy as those players age and, eventually, leave.

"That veteran group also helps drive what the younger group turns into," Matheny said.

"I don't blame him, but I don't like it. I thought we created a really good atmosphere and he had to weigh what was most important to him."

For now, as the Cardinals wait for their young players to take the baton, their best hope is bounce-back seasons from the core.

Wainwright already built optimism for 2016 by returning from a ruptured Achilles tendon to pitch in relief late last season. He struck out 20 batters and walked four in 28 innings. The team doesn't think he'll have any limitations this spring and the year on the sideline might have been just what his right arm needed to recharge for this season. If Wainwright is healthy, he and Mike Leake could be more-than-capable replacements for the tandem of John Lackey, who also left for Chicago, and Lance Lynn, who had season-ending elbow surgery.

When his body is sound, Holliday can still hit. The first part is the worry. After making the All-Star team last season, Holliday returned prematurely from a strained quadriceps and reinjured it. He played in just 73 games in 2015, the first season sunk by injury in what had been an iron man career.

He slugged .410 in 73 games. Much as people fret about the team's lack of power, Holliday paired with Matt Carpenter, Brandon Moss and Randal Grichuk in the middle of the order could manage enough extra-base hits to put that storyline to rest.

Molina's future is a bit hazier due to what have become chronic thumb injuries. The team is hopeful two rounds of surgery will have fixed the problem, but there's no guarantee the wear and tear of catching more than 1,400 major league games hasn't simply caught up to Molina, as it does to so many catchers. Not being able to rely on Molina cuts in multiple directions for the Cardinals because of his vital role in the team's pitching and fielding.

There are other players recovering from injuries who will begin to provide answers this week, as well. Reliever Jordan Walden could give a boost to an already-strong bullpen with his high-90s fastball, but there are questions about his long-term health after he opted not to have surgery for a right biceps injury. Matt Adams missed time with a quad injury and batted just .240 last season. Moss was able to go through his normal offseason workouts, something he couldn't do the previous winter due to his recovery from hip surgery.

Like other veteran teams with World Series aspirations, the Cardinals could prosper or fail based on what happens -- or doesn't happen -- in the trainers' room as much as by what happens on the Grapefruit League fields this spring. Until they start offering some affirmative answers, one big question raised by a former teammate will continue to dog them everywhere they go.