Despite his 4-1 record since joining the Boston Red Sox, Jake Peavy hasn't been great with his new team. The Red Sox's dynamic offense has kept his struggles from becoming an issue. The Red Sox have scored an average of 5.9 runs in his 10 starts. It is pretty hard to lose when your offense is plating six runs per game.
Peavy's ERA is 4.04, which is slightly better than his 4.24 mark with the Chicago White Sox.
However all of his other important pitching numbers are down since he switched his Sox. Peavy's strikeouts per nine innings have gone from 8.6 to 6.3, his walks per nine innings are at 2.6 compared to 1.9 with Chicago.
If the Red Sox continue to tear the cover off the ball in the postseason, then all is well. The team will bash their way to a World Series title. But what happens if they run into a hot pitching staff? A team like the Oakland Athletics or even the Texas Rangers could throw a series of arms at the Red Sox and stifle their potent lineup.
Great pitching will still beat great hitting. Boston has to feel comfortable with the red-hot Clay Buchholz, John Lester and even John Lackey in their postseason rotation, but Red Sox Nation has every right to be concerned about Peavy.
In two previous postseason starts, his ERA is a titanic 12.10.
That said, if he can muster up a solid performance or two, he could be the difference maker in a close series. In the event Buchholz and Lester have battled the opposing team's aces to a stalemate, a lights-out Peavy performance would be huge.
We'll have to wait and see if the Red Sox's bats cool off, and if so, can Peavy step up his game?
Here are two other X-factors who could ultimately hold the key to their team's postseason fate.
Wil Myers - Tampa Bay Rays
The rookie right fielder has had a very good first year in the big leagues. He has 13 home runs, 51 RBI and he's hitting .291 in just 84 games. Stretched over a full season, Myers' numbers would be more than noteworthy.
Even though he has seemingly made a smooth transition to the majors, the postseason is a different animal. Tampa has a one-game lead over the Cleveland Indians and a two-game lead over the Texas Rangers in the wild-card race.
The Rays would have to lose two or three of their final games to be in danger of missing the postseason. All of the teams in contention for the two wild-card spots are hot. The Rays and Indians have won seven in a row, and the Rangers have captured four straight.
If the Rays are to maintain their hold on one of the top two spots, they will need Myers to continue his production. Evan Longoria is the team's leader in home runs and RBI, but the Rays need another bopper.
Myers has the bat to protect Longoria if he hits behind or ahead of him in the lineup. The Rays need a one-two punch, and Myers can complement Longoria.
Matt Kemp - Los Angeles Dodgers
I know Matt Kemp is one of the most talented players in the majors, so it is difficult to buy into him being an X-factor, but he hasn't exactly been a major player for the Dodgers this season.
He's only played in 72 games, and he's hit just six home runs and drove in 33. That's hardly the stat line of a guy of Kemp's stature. Injuries have hobbled him all year, but the Dodgers have still succeeded behind a stellar pitching staff that is tied for the second-lowest ERA in baseball, Yasiel Puig's explosive beginnings and what has quietly been a rock-solid year for Adrian Gonzalez.
As the team heads into the postseason, Puig has cooled off considerably. He's hitting just .231 in September.
The Dodgers need another impact bat in the lineup. Kemp recently returned, and he's been hitting the ball well. He's batting .355 in September, and his production is right on time considering Puig's struggles.
Even though Puig has had a dynamic first year, he is still a rookie. The Dodgers can't necessarily count on him to produce in the postseason. Kemp is a veteran who is more than capable of taking over a series.
The Dodgers need their oft-injured star to play big in the playoffs to win a World Series.
All stats from Baseball-Reference.com.
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