Despite two losses in their last four games, the New England Patriots remain in their usual December position: atop the AFC East and positioned as one of the top seeds in the conference, this time with a 10-2 record. Yet there is unusual concern, because you can’t help but look at Tom Brady’s performance this season and feel like the six-time Super Bowl winning quarterback has lost a step. A closer examination shows Brady’s drop is dramatic enough to make him an average passer at best in 2019, with little hope of returning to elite status.

That sounds crazy, considering Brady has been named to the Pro Bowl 14 times in his 20-year career, but the 42-year-old isn’t as productive as he used to be, and the difference is becoming clear. The future Hall of Famer was 7 for 19 for 82 yards and an interception in the first half of Sunday’s loss against the Houston Texans. He didn’t find the end zone until running back James White caught a touchdown pass with 11 seconds left in the third quarter. Brady got so frustrated he was seen pleading with his receiving corps on the sidelines, demanding they be “faster,” “quicker” and “more explosive.”

A week earlier, Brady mustered 190 passing yards and a touchdown in a 13-9 win over the Dallas Cowboys. And in the game before that against the Philadelphia Eagles, Brady threw for 216 yards and no touchdowns, the first time in Brady’s career he played an entire game and didn’t lead the team in touchdown passes, according to ESPN. Wide receiver Julian Edelman threw New England’s only touchdown pass of that contest, a 15-yarder to Phillip Dorsett in the third quarter. Brady also had 14 incompletions in the first half against the Eagles, a career high.

It’s easy to attribute Brady’s uneven performances this year to the loss of five-time Pro Bowl tight end Rob Gronkowski (retired), the failed Josh Gordon and Antonio Brown experiments and an overall lack of quality receiving options. However, Brady’s rate of “on target” throws has declined from 72 percent in 2018 to 65 percent this season, a dreadful number that is the third-worst among the 26 quarterbacks with at least 300 passes thrown this year. Only second-year pro Kyle Allen and Jameis Winston are worse, per data from Sports Info Solutions.

You could also try to blame some of his inconsistencies on the offensive line. Yet the Patriots’ pass-blocking unit is the sixth-best this season after adjusting their sack rate for defenses faced, per Football Outsiders. And the game charters at Pro Football Focus rank New England’s offensive line as the eighth-best of 2019.

The truth is that Brady has been trending down for a few seasons. His completion rate is on a three-year decline, from close to a career high in 2016 (67 percent) to one of the lowest marks of his career in 2019 (61 percent). His touchdown rate this season (3.7 percent), if it doesn’t improve, would be a career low. Those two components, in turn, are fueling a drastic decline in Brady’s passer rating and adjusted net yards per pass, passing metrics that are best correlated with team wins.

Adjusted net yards per pass is an updated form of a player’s passer rating that gives a bonus for throwing touchdown passes while penalizing for sacks and interceptions, making it very good at telling you the amount of value provided (or not provided) by a passer. Brady is producing 6.3 adjusted net yards per pass this season, just the 17th most among 34 qualified passers and his worst mark since 2013.

Brady was the second-most valuable passer of 2016, per ESPN’s Total Quarterback Rating, only to fall to third in 2017, sixth in 2018 and 17th in 2019. His 52.5 QBR this year suggests a performance good enough to fuel a team to a 8-8 record during a 16-game regular season. If this holds, it would be the lowest QBR of his career, below the 62.1 he recorded in 2013.

Football Outsiders ranks Brady as the 11th-best passer in defense-adjusted yards above replacement and 15th in defense-adjusted value over average, metrics that factor in opponents faced. So even if Brady boosts his raw quarterback rating before the season ends, his upcoming games against mediocre pass defenses such as the Cincinnati Bengals and Miami Dolphins might not reflect much real improvement.

There are other warning signs. Brady’s completion rate falls from 71 percent in a clean pocket to 34 percent when facing pass pressure, the worst mark among qualified quarterbacks, per Pro Football Focus. His passer rating drops from 102.6 to 49.3 in those same situations, one of the worst ratings among qualified quarterbacks. (By comparison, a quarterback will earn a 39.6 passer rating for an incomplete pass.) Brady produced far superior passer ratings under pressure of 71.1 in 2018 and 95.8 in 2017.

No wonder the Patriots’ offense has been underwhelming. New England is averaging less than two points per drive, an average rate for this season and the fifth-lowest rate for the franchise since Coach Bill Belichick took over in 2000. The Patriots are also struggling in the red zone (49 percent, ranking 24th) and in goal-to-go situations (60 percent, 25th).

“There’s some good effort out there,” Brady said after the loss to the Texans. “Guys are doing the best they can do, in my belief. We’re working hard and trying to do the right thing, and sometimes it’s been good. Other times, we obviously still have work we still have to do. That is just part of playing football. Sometimes people have it figured out early and some people, we’re trying to figure it out as we go. That’s just part of it. That is just part of what we’re dealing with.”

Alex Guerrero, Brady’s personal trainer, has speculated that the quarterback might play until he is 46 or 47. But if the current trends continue in these many metrics, the three-time NFL MVP could be done much sooner than that.

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