By Matthew Geagan, CBS Boston

BOSTON (CBS) — Lost in the Patriots quarterback shuffle on Tuesday is the fact that the team’s defense will have to play at least the first six weeks of the season without Stephon Gilmore. The All Pro corner will begin the season on PUP, leaving the New England secondary without one of its best playmakers.

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Gilmore is still on the mend with a quad injury that ended his 2020 season early — and still getting paid under market value on the final year of his contract. It was no guarantee that he would return to his 2018 and 2019 form, but having Gilmore on the field could be the difference of the Patriots defense being pretty good and being really, really good.

The Patriots defense is pretty stacked everywhere else else on the roster. The defensive line will actually be able to stop the run this season, and there are several players who will make life miserable on opposing quarterbacks. From newcomer Matthew Judon to the returning Kyle Van Noy to second-year linebacker Jose Uche — who looked like a guy being shot out of a cannon during the preseason — the Patriots should have a formidable pass rush this season. Dont’a Hightower is also back to lead the rest of the linebackers, and Devin McCourty will be quarterbacking the whole operation for a 12th season.

With Gilmore, New England’s cornerback group could be one of the best in the business. Without him, they’ll still be pretty good, but the grouping will likely have its share of struggles over the first third of the regular season.

J.C. Jackson will remain the team’s No. 1 corner to start the season, and isn’t a bad fill-in for Gilmore. He’s gotten better in each of his three NFL seasons after the Patriots signed him as an undrafted rookie in 2018, and picked off passes nine times throughout the 2020 season as he played nearly 85 percent of the team’s defensive snaps. Quarterbacks completed 59 percent of their passes that went Jackson’s way, which is a bit worrisome, but he is excellent at defending deep balls. Jackson should do well in that No. 1 spot to start the season.

It’s the rest of the corners where the concern arises. Jalen Mills was signed over the offseason to be a Swiss Army defensive back, playing in the slot, potentially at safety, and as the No. 2 corner in an emergency. Not having Gilmore qualifies as an emergency, and Mills is expected to be playing across from Jackson to start the season.

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Mills did not have a great camp and he struggled during the three-game preseason slate. Teams will be locking onto whoever he’s covering over the first six weeks as Mills further acclimates himself to the New England defense.

Jonathan Jones is as solid as they come in the slot, but he’s banged up heading into the season. Joejuan Williams and/or newcomer Shaun Wade could see some playing time in the slot if Jones isn’t at full strength when things kick off. And until the Patriots are at full strength, cornerback is a position that teams will be able to pick on.

There is a silver lining to the first six weeks of the season: The Patriots get to face some extremely inexperienced quarterbacks over that span. Of course, the most accomplished quarterback is also in the mix, with Tom Brady and the Buccaneers come to town in Week 4. That meeting will likely be a bloodbath for the New England secondary, as it will be for other secondaries throughout the NFL when they face Brady and the Bucs.

But outside of Brady, here are the quarterbacks that the Patriots will face over the first six weeks: Miami’s Tua Tagovailoa in just his 10th career start; Jets rookie quarterback Zach Wilson in just his second career start; New Orleans’ Jameis Winston in his third start with the team; Houston’s Tyrod Taylor (unless something changes on the Deshaun Watson front); Dallas’ Dak Prescott in his sixth game since coming back from an ankle injury.

That isn’t too bad, outside of the seven-time Super Bowl winner in Week 4. Tampa Bay will be the best offense they face all season, and then there is a sharp drop-off to the next team, which is likely the Saints. But in Week 3, New Orleans will still be getting used to life after Drew Brees, and though Winston can make teams pay with the deep ball, he also likes throwing the ball to opposing defenses.

The corners will be susceptible to breakdowns over the first six weeks without Gilmore, and life will certainly be a lot more difficult for the defense as a whole. But with some big improvements elsewhere on the defense, the Patriots should be able to survive the first six weeks without their All Pro cornerback. Let’s just hope he does indeed return and is ready to play at his usual level come Week 7.

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