As it is, they're already on pace to allow 46 sacks this year. That's five more than they've ever given up in a given season, with their highest total being the 41 they allowed back in 2001, which was the year Brady first replaced Drew Bledsoe and that total was accumulated over just 15 games. Other than that, they've never allowed more than 32, which came back in 2011. From there you'd have to go all the way back to 2003 when New England gave up the same total.
While this team currently has a myriad of issues on the offensive side of the football, looking at the numbers it starts to make sense. Brady's been sacked on first down eight times this season, three more than he was in that situation all of last year. That's played a part in the fact of the 169 second downs they've attempted this year, they've faced 2nd-and-7 or longer 108 times (64% of their plays). They've also failed to gain a yard rushing the football on 2nd down 14 times this year, which now typically translates into long yardage situations on third down. As it stands at this point, the Patriots overall are just 35-of-105 converting on third down this season.
Looking closer you can see one glaring issue as the Patriots have faced 3rd-and-7 or longer on 51 plays (49%). Since that situation usually turns it into an obvious passing down, teams are teeing off on him and he's seen a lot of pressure as a result. Of those 51 plays, they've converted just 13, and Brady's been sacked on 5 of them. They've brought him down 10 times on third down so far this year, just four shy of the 14 sacks in that situation all of last season.