While the World Series is shaping up to be a memorable classic, the MLB offseason has already begun for the league's 28 other organizations.  At this point, most front offices are well into the roster-construction phase of the offseason, building up for 2015.

Though free-agency transactions will predominate this winter, trades also play a critical role in jump-starting a team's plans.  As the Kansas City Royals have illustrated, bold winter transactions can pay off for teams teetering on the brink of contention.

Any trade is likely weeks or months away from materializing, but there are already rumors surrounding certain players who may or may not be on the market.  Read on to see which names could help shape next season's pennant race.

Phillies Shopping Hamels?

The Philadelphia Phillies have stubbornly held on to delusions of contending with their aging core, but it appears general manager Ruben Amaro Jr. may have finally accepted his team's harsh reality.  If the Phillies do embrace a full rebuild, CBS Sports' Jon Heyman reports that ace lefty Cole Hamels could be on the move if someone is willing to meet Philly's price:

Hamels could be dealt, but only for a very steep price, executives on other teams say they've been told.

Hamels himself has been told by the Phillies that they would love to keep him but also that it's possible their situation could cause them to have to reconsider that. While the Phillies obviously would prefer to hold on to Hamels, one competing executive put it this way: "That's their only [valuable] trading chip."

Hamels possesses a limited no-trade clause in his contract, and reporters near the team are suggesting that he may be updating his list in anticipation of imminent movement:

Still, with the likes of Max Scherzer, Jon Lester and James Shields figuring to attract the most attention on the free-agency market, it will likely be several months before any team even considers meeting the Phillies' price tag.  Amaro has no incentive to simply pawn off his most valuable trade chip, especially when he may hold more leverage over a contending team at the midseason trade deadline.

Philadelphia's depleted farm system needs a significant haul for a premium lefty like Hamels, so an eventual trade seems likely.  But with an unusual crop of high-end free-agent starters available, the timing this offseason may not be right.

Davis Expendable?

Chris Davis arguably regressed more than any other player this season, falling from 53 home runs and a .634 slugging percentage in his MVP-caliber 2013 campaign to 26 dingers and a paltry .404 slugging percentage this season.  With Davis returning to his low-average, strikeout-heavy ways, ESPN's Jim Bowden (subscription required) suggests that lefty slugger may now be expendable to the Baltimore Orioles:

The Orioles are prepared to listen to offers on Chris Davis after Steve Pearce's breakout year and in light of the fact that Davis is a free agent at season's end. Plus, if someone wants to take a chance on Matt Wieters coming back from Tommy John surgery, the O's will listen to them as well. The Tigers are going to make a strong run on improving their bullpen, which will include the pursuit of free-agent left-hander Andrew Miller, who will be one of the most sought-after free agents on the market. 

Additionally, Davis was suspended 25 games at the end of the season for a positive amphetamines test, ending his disappointing campaign with a black eye.  In fact, because of the Orioles' ALCS sweep at the hands of the Royals, Davis' exile actually extends into the beginning of the 2015 campaign:

More pressingly, Baltimore must decide whether they want to take Davis to arbitration, where Davis is likely to receive a bump from his current $10.3 million salary, albeit a smaller raise than he received after last season.  For the small market O's, it may make sense to sell high on Davis while the sheen of 2013 remains, a season that looks like a flagrant outlier in his career profile.

Upton and Heyward on Block?

The Atlanta Braves have been one of the league's most consistent franchises over the past two decades, and with a young, All-Star laden outfield, the Braves looked poised to challenge for the National League crown.  But after a disappointing 79-83 campaign, MLB.com's Mark Bowman believes that Atlanta could look to rebuild by dealing two of their most valuable trade chips from that outfield:

Staring at the possibility that both [Jason] Heyward and [Justin] Upton could both exit via free agency next year, the Braves have to evaluate whether it would be wise to trade at least one of those corner outfielders in exchange for a group of players who could either make an immediate impact or, maybe more importantly, fortify the club as it attempts to enter SunTrust Park in 2017 with a strong product.

Upton and Heyward are both among the most promising all-around outfielders in the game, so it seems unlikely that the Braves will be able to retain both within their budget, especially when considering the extensions they handed to Freddie Freeman, Craig Kimbrel, Andrelton Simmons and Julio Teheran.  In fact, there is already buzz connecting the right fielder to the Boston Red Sox:

Cafardo and Edes both wrote about Sox/scouts not liking Yoenis Cespedes' defensive work/effort. Both mention possible Jason Heyward target.

— Red Sox Stats (@redsoxstats) October 16, 2014

It is too early in the process to pin down a clear destination for either Upton or Heyward, but it seems unlikely that both will make it into the Braves' Opening Day lineup.  Atlanta will want to remain relevant as it moves into its new ballpark, but financial constraints will likely force the Braves to endure a tough loss in this scenario.