This is your annual reminder -- as if you needed one -- that Opening Day rosters mean bubkus in the big picture of a 162-game season. Pennant races will be decided not by the groups being sorted out in Florida and Arizona camps today but by roster maneuvering that takes place as injuries and unexpectedly poor performance present needs in the future.

If a team is both lucky and prepared, the upgrades will come in-house, with some kid rising to the occasion. And that's the notion behind this list of as-yet-unproven prospects who could help contending clubs in 2017.

This list, of course, is not exhaustive, nor could it reasonably be (show me the pre-2016 analysis that claimed Ryan Merritt, of all people, would get the starting nod on the day the Indians clinched the AL pennant). These are just a dozen guys who won't be on Opening Day rosters but whose timetables could align nicely with needs. 

1. Gleyber Torres, SS, Yankees

Increasingly the young man's game that this is, it's not crazy to think that some precocious producers could keep the Yanks in the AL Wild Card hunt in the second half. And this club has such a nice stash of young players right now that it's hard to single out one guy. Clint Frazier could just as easily be on this list, or perhaps Justus Sheffield, who I profiled here. But Torres, acquired from the Cubs in last summer's Aroldis Chapman trade, is a particular source of fascination right now because he lit up the Grapefruit League, was MVP of the Arizona Fall League and could make like Carlos Correa in beginning his age-20 season at Double-A and ending it in the big leagues. 

Fans, of course, want to see him right now, with Didi Gregorius on the shelf for the first month of the season. The Yankees, though, probably did the wise thing in not jumping Torres up two levels and starting his service-time clock to be a temporary fill-in. 

This will be fascinating, though, because between Gregorius' injury and Chase Headley's brutal slow start to 2016 (he had a sub-.600 OPS around Memorial Day), the potential is there for Torres to get the call midseason. He could play anywhere in the infield. 

2. Austin Meadows, OF, Pirates

The assumption for now is that we'll only see Austin Meadows if the Pirates are out of contention and move Andrew McCutchen this summer. But never underestimate baseball's general weirdness and unpredictability. Maybe the 21-year-old Meadows comes up as a reserve at all three outfield spots. Maybe an injury to Cutch, Gregory Polanco or Starling Marte thrusts him into the bigs. Or maybe the Buccos are in the Wild Card hunt and move McCutchen, anyway, because they find a deal too good to turn down (they did do the simultaneous buy-and-sell thing last summer, after all).

Whatever the case, Meadows, who will open with Triple-A Indianapolis, has shown the discipline and developing power to lead you to believe his bat will play in the big leagues, though he has battled injuries in his Minor League career.

3. Francis Martes, RHP, Astros

There had seemed an outside chance the Astros' top prospect might crack the Opening Day rotation with an electric camp, but instead he'll begin the year in the Minors, as expected, further refining the changeup to pair with his mid-90s fastball and plus curve. That said, he figures to be up before long on an Astros team with some uncertainty in the rotation.

Or, you know, he could be used in a trade for Jose Quintana or another established starter. We shall see.

4. Cody Bellinger, 1B, Dodgers

Would have been fun to see Bellinger -- a first baseman -- force his way into the Dodgers left-field picture with a sizzling spring. With Adrian Gonzalez, who is under contract through 2018, blocking him at first, there's little doubt Bellinger (who is really sharp at first) could be at least an adequate defender in the outfield, and his power bat rates as a potentially big asset. Alas, when Gonzalez was injured early in camp and then left for the World Baseball Classic, Bellinger struggled for a couple weeks with the added at-bats, running into strikeout struggles against better competition. It happens, though scouts felt he adjusted well as the spring rolled along.

Anyway, keep an eye on Bellinger at Triple-A Oklahoma City. He logged a .271/.365/.507 slash in 117 games at Double-A Tulsa last year, and while Gonzalez has generally been a lock for 155-plus games, outfield opportunity could arise on this win-now club. 

5. Tim Tebow, OF, Mets

Just kidding…

5. Amed Rosario, SS, Mets 

He's 21 and has yet to play a full season at Double-A, but he's definitely on the big-league radar, especially after a splendid showing in the Grapefruit League. After getting on base at a .374 clip with 24 doubles, 13 triples and 19 steals in 479 at-bats between High-A and Double-A last year, Rosario made the biggest jump of any player on MLB Pipeline's preseason Top 100 Prospects list from 2016 to '17, leaping from No. 79 all the way to No. 5. His defense -- particularly his range and arm -- rates as an impactful asset.

Asdrubal Cabrera was terrific for the Mets last year, and Jose Reyes, who will continue to fill in for the injured David Wright, was surprisingly solid at third. But it's not hard to imagine age, offensive performance, injury or defensive concerns creating opportunity on the left-hand side of that Mets infield this season, and Rosario might be ripe to step in. 

6. Jeimer Candelario, 3B, Cubs

This guy is totally blocked right now, but what does that matter when we're talking about the Cubs? Joe Maddon will throw him in the starting rotation just to get his bat in the lineup every fifth day, and it will somehow work.

In reality, even with Kris Bryant and Anthony Rizzo on the infield corners and the outfield corners spoken for thanks to Bryant, Kyle Schwarber, Ben Zobrist and Jason Heyward, the season has a way of evolving to the point where the best bats find their way into the lineup. And Candelario's Minor League track record, which includes a 12.3 percent walk rate and .333/.417/.542 slash in 76 games at Triple-A last season, insists his bat could force the issue. 

Or hey, maybe he ends the season in somebody else's starting lineup if and when the Cubs go out and acquire some shiny new pitching.

Cubs people have been really, really pleased with the way Cendelario, Ian Happ and Eloy Jimenez performed this spring (though Jimenez is currently shut down with a bone bruise). They feel they've effectively refuted the assumption among some that their position-player pipeline is finally running dry. The Cubs just keep coming. 

7. Brent Honeywell, RHP, Rays 

The Rays aren't exactly favorites in the American League East, but their depth of pitching gives them sleeper potential if their offense and bullpen click.

Jose De Leon, the high-profile prospect acquired in the Logan Forsythe trade, is a pretty obvious entry for this list, though some scouts are less sure of his front-of-the-rotation potential than others. He'll begin the year at Triple-A, and the Rays will carefully manipulate his service time before adding him to what looks to be a strong rotation. 

That said, also keep an eye on the screwball-tossing Honeywell. Because he was a second-round draft pick and not a high-profile trade acquisition, his name might not be quite as well known as that of De Leon at the moment. But he's got a good arsenal, had a 4.68 strikeout-to-walk ratio at High-A and Double-A last year and is another arm that could upgrade this club in-season.

The Rays might deal from their Major League starting depth, which would create added opportunity for either of these guys. 

8. Brad Zimmer, OF, Indians 

It goes without saying that the Indians have a lot riding on this 2017 season, and they're riding into it with an iffy outfield situation centered around Michael Brantley's iffy shoulder situation. This is another one where it's not hard to imagine a need arising in-season, and though Zimmer has some contact issues to iron out, his encouraging spring camp, which emanated from some mechanical changes at the plate last season is a potential indicator that his speed-defense-patience portfolio is nearing big-league readiness.

Catcher Francisco Mejia, who would have been the key piece acquired by the Brewers in the vetoed Jonathan Lucroy trade last summer, is another candidate here for a win-now club that struggled to find offense out of the catcher's spot last season. But he's probably on a slower path on account of his defensive position. Keep an eye on speedy outfielder Greg Allen, too.

9. Rafael Devers, 3B, Red Sox

Sam Travis might qualify here. He's lit up the Grapefruit League for the second straight spring season, this time after his 2016 ended abruptly after 47 games because of knee surgery. But because Hanley Ramirez's shoulder injury has affected his ability to play first, Travis has a shot at the Opening Day roster.

But further down the ladder is Devers. He'll be looking to follow the Andrew Benintendi Blueprint, which goes as follows: Spend a season at Single-A, get invited to big-league camp, move up to Double-A and grab a spot on a pennant-chasing Red Sox team with a positional need.

Devers' ability to impact this ballclub in 2017 is likely as dependent on Pablo Sandoval's performance as it is on his own, and the slimmed-down Panda is having a great spring camp. But certainly, it's a wait-and-see situation with Sandoval this season, and Devers' quick bat and improved D merit monitoring. 

10. Tyler O'Neill, OF, Mariners 

It's admittedly hard to keep track of who's still in this organization after another winter trade frenzy, but, yes, O'Neill, a 2013 third-rounder who was named Southern League MVP last year, remains an M.

He hit 24 homers with a .293/.374/.508 slash in Double-A last year and is said to move around pretty well in the outfield despite his background as a catcher. The son of a former Mr. Canada, O'Neill is short but built, and while the Mariners, who are desperate to get back to October for the first time since 2001 (hence the aforementioned trade frenzy), feel good about their improved athleticism in the outfield after the additions of Mitch Haniger and Jarrod Dyson, it's possible O'Neill could play himself into the mix by season's end. 

11. Sandy Alcantara, RHP, Cardinals 

A 6-foot-4 right-hander who has filled in a bit of his beanpole frame, Alcantara has plus velocity and promising secondary stuff. He struck out 11.2 batters per nine in Class A last year, and, while he hasn't pitched above that level, the Cards have been known to bring pitchers straight up from Double-A before and could have a need with Alex Reyes out of the mix. General manager John Mozeliak was not shy about saying Alcantara could conceivably pitch in the bigs this season.

12. Yohander Mendez, RHP, Rangers

There are questions about the back end of this rotation going into the year. Obviously, Andrew Cashner and Tyson Ross have health issues attached to them, and the partial UCL tear suffered by Chi Chi Gonzalez depleted the Rangers' depth a bit. But the 21-year-old Mendez, who made his big-league debut last year and had a 2.19 ERA and 1.02 WHIP in 111 Minor League innings, presents upside potential if he can sharpen his command at Triple-A early this season.

The Panama-born Ariel Jurado, 20, is another possibility for the Rangers rotation as the season evolves.

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Anthony Castrovince is a Sports on Earth contributor, MLB.com columnist and MLB Network contributor. Follow him on Twitter @Castrovince.