World Series 2013: Biggest X-Factors in Exciting Fall Classic

The Boston Red Sox and St. Louis Cardinals will line the 2013 World Series with star power, and both teams will be looking for star players like David Ortiz and Carlos Beltran to perform.

However, just as vital to the teams' chances will be getting a strong boost from various X-factors.

These guys aren't stealing the spotlight heading into the series but will be counted on to fill key roles. There is also a chance that one of them will be standing right in the middle of the spotlight at the series' end. 

Daniel Nava, Red Sox

Switch-hitting outfielder and first baseman Daniel Nava has found a curious place on the Boston bench. The 30-year-old had a solid season with a .303 average, 66 RBI and 12 home runs. However, he has taken a back seat to Jonny Gomes in the postseason and has just 11 at-bats in these playoffs.

What has made this curious is the fact that Boston has been facing a steady stream of right-handers and Nava has proven to be the superior option in that case. He hit .322 with 10 home runs against right-handers this season.

Perhaps Boston will continue to roll with Gomes, but Nava has a chance to make a big impression and earn at-bats back. After all, each of St. Louis' starters throws from the right. 

If Nava can get hot, it will give Boston a formidable lineup for the diet of right-handed starters and give the Red Sox a quality bench option with Gomes. 

Allen Craig, St. Louis Cardinals

Allen Craig would fall more into the star category were he not coming back from a foot injury.

Obviously, this is great news for the Cards. Craig hit .315/.373/.457 during the regular season. However, his absence has been a lengthy one. Craig will now have to try to get his timing back on the biggest stage of his sport.

It would be silly to expect Craig to come back and instantly start producing like this:

Another reason Craig is an X-factor is that it remains to be seen how his foot will respond to the return to action and whether or not the slugger will be able to play first base when the series heads to St. Louis. 

If Craig can stay healthy and produce anywhere near the level he was before his injury, St. Louis will be in good shape. 

Xander Bogaerts, Boston Red Sox

Xander Bogaerts is a star in the making. When he starts Game 1 at third base for the Red Sox, less than a month removed from his 21st birthday, Bogaerts will supplant Babe Ruth as the youngest Red Sox to ever start a World Series.

You wouldn't be able to tell this by his postseason performance. Bogaerts has reached base in eight of his 11 plate appearances. With Will Middlebrooks in a postseason slump, this has been a key addition to Boston's lineup. 

Bogaerts doesn't have the same kind of power as Middlebrooks. However, it's not like the Red Sox are lacking for power in the lineup, and Bogaerts' ability to get on base is a huge asset. 

If Bogaerts continues to be unfazed by the massive stage, his elite talent could lead to him stealing the spotlight in this Fall Classic. Obviously, that would be a huge boost to an already potent Boston lineup. 

Randy Choate, Cardinals

As I mentioned above, the Cardinals will feature a starting rotation of nothing but righties. This puts a huge emphasis on Randy Choate.

Choate is a situational left-handed reliever, and he is a good one. He made 64 appearances this season and posted a 2.29 ERA, and that came against almost nothing but opponents' best left-handed hitters. 

In five postseason outings in this run, Choate has yet to allow a single baserunner. 

The Red Sox have plenty of left-handed power in their lineup, and the Cardinals will be leaning heavily on Choate in big situations in this series. 

If he continues his flawless postseason run, the Cardinals' bullpen will be in great shape.