Jeff Saturday breaks down Tom Brady's late interception, saying things are starting to speed up for the Pats, causing their mistakes. (1:00)

Father Time, you might have heard, is undefeated. We've known all along that he was coming at some point for Tom Brady. And as of midseason, it looked like 2018 might be the year.

We've been waiting for Brady's decline for years now, and the assumption has always been that when it came, it would be swift and painful. That's because so many recent top quarterbacks played well into their thirties and then suddenly fell off a cliff in their final seasons. Here are some examples, using Football Outsiders' passing DVOA (defense-adjusted value over average) metric:

Peyton Manning started to lose it in the middle of a season. In 2014, at age 38, he was still the top quarterback in the league in passing DVOA through Week 9. Then in Weeks 10 to 17, he was merely average. The next year, at the age of 39, he ranked a dismal 36 out of 37 quarterbacks in passing DVOA in his final season.

Brett Favre finished fourth in DVOA in 2009 at age 40, then crashed to 32nd out of 34 quarterbacks in 2010 at age 41.

Rich Gannon was MVP in 2002 at the age of 37. The next year, at 38, he ranked 27 out of 37 quarterbacks in passing DVOA.

Steve McNair ranked 35th out of 38 quarterbacks in his final season, 2007.

Troy Aikman ranked 33rd out of 40 quarterbacks in his final season, 2000.

Dan Marino ranked 23rd out of 40 quarterbacks in his final season, 1999.

Not every older quarterback had a decline like this. John Elway and Kurt Warner each had declines in the middle of their careers, then rebounded and played well all the way to the end. Jim Kelly declined slowly over the course of his final four seasons. Warren Moon was up and down from the age of 37 on. And of course, Drew Brees, 39, hasn't hit any kind of decline phase yet.

What is notable about Brady's early-season decline is that he didn't collapse. The Tom Brady of the first half of this season was still an above-average NFL quarterback. But there was no question he was not playing up to his previous standard. Brady, 41, had gone from MVP-level performance to top-10 quarterback, maybe top-12.

Or as I wrote after the New England Patriots' Week 10 loss to the Tennessee Titans:

The Tom Brady decline is confusing because we all thought it would be "fall off the cliff" when it came. But it's been very gradual. Brady is currently 12th in pass DVOA and 11th in ESPN QBR. He's still good, but he's not the Brady we're used to. https://t.co/IiZPSUkDO0 - Aaron Schatz �� (@FO_ASchatz) November 13, 2018

Well, "the Brady we're used to" came back after the Patriots' bye in Week 11. Even if we include Sunday's relatively mediocre performance at the Pittsburgh Steelers, Brady has been the best quarterback in the league since Week 12, according to both ESPN QBR (80.9) and Football Outsiders passing DVOA (39.4 percent).