The Sox have a really, really tough schedule to finish up:
3 v NYY
3 @ SFG
3 @ LAD
3 v BAL
3 v CHI
3 v DET
4 @ NYY
3 @ TB
3 v NYY
3 v BAL
3 v TOR
2 @ COL
3 @ BAL
Bolded teams are at or below .500. So, of the Red Sox final 39 games, 11 are against losing teams, 28 are against better than .500 teams, all of which are contending teams in the PS hunt. They do have an extra series at home, which should help (18 away games, 21 home games), but if they're going to win this division or even make the PS, they're going to really have to earn it.
The biggest boost that the Sox could get would be a healthy Buchholz in 2 weeks.