The easier part of the schedule hasn't gone exactly as the Red Sox planned it.
To be fair, 6-4 is not a bad record. It's just not really good enough against the Royals, Athletics, and Orioles when you're taking on the likes of the Yankees and Rays for much of the year. If the Sox want to finish this stretch feeling good about it, they've got to win a 4-game series against the Indians in Cleveland.
Like with the Orioles, this should not be that hard. They have bad hitters, bat starters, bad relievers, and bad fielders. They dwell in the cellar of most of the big statistical categories, and really should not be giving a good Red Sox team much of a run for their money. But, as mentioned, the Sox haven't been entirely living up to those expectations of late.
What might favor the Red Sox this time is how the starters are matched up. The Indians have two starters with a good ERA: Mitch Talbot, and Fausto Carmona. Of the two, Carmona is the one whose peripherals support that he's actually pitching well—Talbot's nearly identical K and BB/9 are hidden behind a low BABIP—so he has a good chance at taking the first game tonight if Matsuzaka doesn't show up to play.
But from there on, things look good. The Red Sox' biggest question mark in Tim Wakefield will be matched up against their disaster starter David Huff, so even if Wakefield does blow up, the Sox could well still be right in the game. Then the Sox have their top-2 in Buchholz and Lester coming up against Justin Masterson and Talbot. The Sox can hide their depleted outfield with a crew of lefties against Masterson, who can't get them out, and the strong Sox lineup that likes to wait for their pitch and can foul a ton off in the zone could give Talbot fits.
Daisuke and Wake will likely be aided by facing another unimpressive lineup. The Indians really only have one legitimately good-great bat in Shin-Soo Choo. Austin Kearns' season to date comes with a BABIP over .400, and Russel Branyan is above average, but doesn't get on much. Ultimately, there's just not a ton to be frightened by.
The Indians relievers are an interesting group. A cursory glance shows a lot of earned runs. A slightly deeper glance shows a lot of bad defense behind them, but also reveals some big luck on fly balls staying in the yard. Generally speaking, too many balls in play and too many walks are not the recipe for success in a reliever, and should hurt the Indians in the long run. (And, yes, that was a patheticaly transparent progression from ERA to FIP to xFIP)
If we've learned anything from the last few series, it's that we can't just go in and expect to win against bad teams. The Royals faced this same set of starters, and managed to split the series. But if the Sox go into Cleveland and play up to their abilities, it's not unreasonable to say that 3 wins should be the minimum. Maybe Carmona takes the first one, or they steal another one on a hot night, but really, they should win this series.