Boston certainly has the upper hand as the series heads back to Fenway Park. However, the Cardinals have been in tough spots before, and they have the talent and postseason experience to come back from this deficit.
In reality, anything can happen based on which team can hit, pitch and field better over the last couple of days of the season.
Here is a look at the last two games of the World Series with predictions for each.
When: Wednesday, Oct. 30, at 8:07 p.m. ET
Where: Fenway Park, Boston
Although Adam Wainwright could not shut down the Red Sox in either of his two starts, Michael Wacha has a chance to accomplish this feat for a second time in Game 6.
The rookie has been incredible in the postseason, winning all four of his starts with a 1.00 ERA. While he struggled a bit with his control in Game 2, he still only allowed a David Ortiz two-run homer in six innings.
St. Louis will hope that he can keep the magic going and win for a fifth time in as many games in the playoffs.
Boston certainly has the ability to get runs across, but they will need to get more production out of everyone not named Ortiz. While Big Papi has hit .733 this series, the rest of the lineup is only batting .151.
That might not be enough for John Lackey, who has had an up-and-down postseason so far. He has a 2-1 record in three starts, but only once did he allow fewer than three runs. In this marquee pitching matchup, he will have to be at his best and hold the Cardinals to only one or two scores in the game.
Unfortunately, you can expect the St. Louis bats to take advantage of Lackey's tendency to give up home runs, and extend the series to seven games with a win in Boston.
Prediction: Cardinals 3, Red Sox 1
Game 7 (If Necessary)
When: Thursday, Oct. 31, at 8:07 p.m. ET
Where: Fenway Park, Boston
The projected starters for Game 7 are Joe Kelly and Jake Peavy, which is quite a drop in quality from the previous game.
While Kelly was actually the Cardinals' best starter during the regular season, he has been shaky in the playoffs and only made it out of the sixth inning once in four starts. Meanwhile, Peavy has not even seen the fifth inning in his past two starts.
Of course, Game 7 rules dictate that this will not matter too much. In the final game of the year for both teams, every pitcher is available and both starters will have a short leash.
This puts more pressure on the bullpens, which gives Boston the advantage. Not only have the Cardinals' relievers been unreliable (with the exception of Trevor Rosenthal), but the Red Sox have also made a habit of knocking runs in late throughout the postseason.
If Ortiz is not the one coming through with a big hit, you can expect experienced hitters like Dustin Pedroia or Mike Napoli to help the squad earn its third World Series title in 10 years.
Prediction: Red Sox 6, Cardinals 4
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