World Series 2014: X-Factors to Watch for Giants vs. Royals

One of the most crucial components in the World Series every year is just one player who can shift momentum. The 2014 World Series between the Kansas City Royals and San Francisco Giants has proved to be no different.

In Game 1, it was Hunter Pence who changed the outlook with just one swing in the first inning. Omar Infante put an emphatic stamp on Game 2 with a long ball of his own to cap off a five-run sixth frame.

For either team to eventually take the World Series, it will need players outside of the known superstars to step up. Both franchises have unheralded players who have propelled them to this point, but which team will have them do the same in the Fall Classic?

Still in the midst of the World Series, here's a look at the X-factors for the Royals and Giants.

Omar Infante

Just how rare was the homer for Infante in Game 2? In 159 postseason plate appearances with the Detroit Tigers and Royals, he now has one four-bagger to his name.

He struggled mightily in the American League Division Series, but he has recovered in the last several games. After hitting .308 in the ALCS, Infante has two extra-base hits against the Giants—both were his first in the World Series.

General manager Dayton Moore spoke about what Infante adds to the team, per Andy McCullough of The Kansas City Star.

"He’s got some big hits for us,” Moore said. “He’s made some big plays for us. I think he can tell you that he’s not satisfied with his year. It seems like to me, he’s always gotten on base at the right time or gotten the big hit. He’s been in the middle of a lot of our success."

After having success against Jake Peavy and the Giants bullpen, Infante will have to continue coming up big for the Royals. Holding a .333 average thus far in the World Series, his consistency will be necessary to drive in potent batters ahead of him in the lineup.

Giants Bullpen

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One of the biggest storylines coming into the World Series was how deadly the Royals bullpen has been. But the Giants felt comfortable with their own lethal bullpen—or so they thought.

In Game 2, the pen came unraveled as Hunter Strickland gave up yet another homer following Peavy's outing. Strickland failed to record an out, giving up the two-run bomb to Infante. Mark Zuckerman of CSN pointed out the struggles for Strickland thus far:

But the bullpen has typically been a strength during the playoffs for the Giants. Names like Javier Lopez and Jeremy Affeldt have consistently passed the torch to get to the end of the game, but neither was given the chance.

Manager Bruce Bochy referenced his scuffling bullpen following Game 2, per Jim Caple of ESPN.com:

"

With our pen, I know they've had a couple of hiccups. That was a tough game for them [Wednesday] night, but these guys are the reason we're here. You're still going to need them, because you can't push your starter past where you think he should be at.

Ideally, your starter does get you deep and helps you out there. But at the same time, I don't want to put any added pressure on him. We think we're going to be fine.

"

In order for the Giants to win their third World Series in the last five years, Bochy will need his bullpen to come through again. If Tim Hudson or Ryan Vogelsong struggles, more pressure will be on the relievers to give the offense a chance to catch up.

Without that stability in the back end, San Francisco's luck in even years might just run out.

James Shields

How can a staff ace be considered an X-factor? Struggling in nearly every postseason start this year will change expectations slightly.

James Shields earned the nickname "Big Game James" thanks to his performance in the spotlight during his nine-year career. Unfortunately, the pressure seems to be getting to Shields in the playoffs, as ESPN Stats & Info notes:

The Game 1 performance for Shields was a tough one to swallow, but his struggles have been widely publicized throughout the playoffs. During his four starts, Shields holds a 7.11 ERA and a total of four home runs.

Jeff Passan of Yahoo Sports points out the stark difference from his regular-season numbers:

Shields might be one of the marquee names for the Royals, but struggling again would be costly. With a chance for the first World Series in 29 years hanging in the balance, Shields will have to answer the bell on the mound.

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