Change is coming for the Patriots this offseason. Every day this week, we'll react to one area of the team that either has already undergone a shift, is in the process of shifting, or will be shifting soon. Today we'll look at what changes could be taking place on the roster because of retirements.

There's a saying in the NFL that if you're talking about retirement, you've already made up your mind.

Yet Rob Gronkowski stuck around for 2018 after admitting he'd wrestled with the idea following Super Bowl LII. Ben Roethlisberger is still active after kicking around the idea of hanging 'em up off and on for a decade. Few have thought about retirement more than Brett Favre, who mentioned the possibility all the way back in 2002 but played until 2010.

So just because Gronkowski and Devin McCourty have acknowledged they could be retiring prior to next season doesn't mean they will. But what if . . . ?

Let's start with Gronkowski, since that decision could be imminent. He told reporters that he'd know a couple weeks after Super Bowl LIII whether or not he'll be playing again.

He played in 13 games in 2018, caught 47 passes for 682 yards, but saw his production soar in critical moments in the postseason, finishing with 13 grabs for 191 yards in three games. Late against the Chiefs in the AFC title game and against the Rams in Super Bowl LIII, opposing defenses had no answer for him.

There would be no one-for-one fill-in for Gronkowski if he called it quits, even at this stage of his career. He's that unique. The Patriots would quickly need to discover another mismatch pass-catcher in big spots. Julian Edelman, still under contract for 2019, would, of course, factor into the equation. Running backs James White and Rex Burkhead would also likely have to pick up the slack in the passing game.

But what about finding someone who could cut into any receiving production lost and contribute as an in-line blocker? Dwayne Allen and Jacob Hollister, both under contract for 2019, haven't proven that they can be reliable options in that regard at this point. Free agency could be an option, though. The oft-injured but talented tight end Tyler Eifert is set to hit the market, as are veterans Jared Cook and Luke Willson.

This year's draft class provides what seems like an opportunity for the Patriots to find a long-term replacement for Gronkowski. Iowa, home of Bill Belichick pal Kirk Ferentz, has two players entering the draft who could be taken in the first round in T.J. Hockenson and Noah Fant. Then there's Nick Saban pupil Irv Smith, who could also be an option as a two-way threat late in the first round.

Would any of those tight ends give the Patriots what Gronkowski would? Probably not. But, at a critical position in the Patriots offense, it would give the Patriots something they're lacking at the moment: hope for the future.

McCourty, meanwhile, could be just as hard to replace if the Patriots' hands were forced.

What he does to coordinate the secondary on a snap-to-snap basis is critical to the overall operation. He's the voice of the defensive back group and a longtime captain. And he's continued to provide high-level play whether in the deep portion of the field, in the box, or in man-to-man coverage of backs and tight ends. Patrick Chung is widely regarded as one of the team's most versatile players, but McCourty is starting to pick up almost as many roles as his teammate as he plays closer to the line of scrimmage more and more, allowing Duron Harmon to take on work deep down the field.

Like Gronkowski, there would be no one-for-one replacement for a player who does as much for the Patriots defense as McCourty does. Bill Belichick could try to fill the spot in the secondary with one of a couple of Alabama products hitting free agency this offseason: Ha Ha Clinton-Dix or Landon Collins, though the expectation is that both will cost a great deal as good players firmly in their primes.

The incoming rookie class has high-end safeties from a couple of programs Belichick respects. Alabama's Deionte Thompson and Delaware's Nassir Adderley look like ready-to-go free safeties, while Mississippi State's Johnathan Abram and Washington's Taylor Rapp look like they'll be impactful box safeties for years to come. All could go in the first two rounds.

If McCourty does indeed retire, unless the Patriots invest early in the draft at that position, it seems like they would roll with three corners instead of going with their "big nickel" with three safeties. That would allow Harmon and Chung to split the traditional free and strong safety roles.

Obviously, it'd be less than ideal for the Patriots if either Gronkowski or McCourty retired, but those are possibilities for which the team may have to prepare. And even if change isn't coming on either front, contingencies very well could be.

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