Patriots Coach Bill Belichick, left, offensive coordinator Josh McDaniels, center, and quarterback Tom Brady watch the final minute of their playoff loss to Tennessee on Saturday night in Foxborough, Mass. Steven Senne/Associated Press

FOXBOROUGH, Mass. — The fog hung in the air and swathed the field of Gillette Stadium, muting the colors and making you think, inevitably, of ghosts. It all felt like … the past. The New England Patriots were clearly not quite what they once were, and the Tennessee Titans yanked this AFC wild-card game away from them and into the future.

Outside before the game, the longtime Patriots faithful hunched in the rainy parking lot trying to coax a flame out of damp charcoal. You got a similar feeling watching Tom Brady try to get points out of his offense, trailing 14-13 deep in the fourth quarter, unable to make a big play. Meanwhile there wasn’t a thing anybody could do to stop the Titans’ Derrick Henry, 6-foot-3, 247 pounds and a fresh-legged 26 years old. When the final score of 20-13 was posted on Saturday night, ending the Patriots’ season and possibly an era, it felt like many things all at once – flat, sudden, yet inevitable, and a long time coming, too.

“It’s just like a crash landing, man,” said safety Devin McCourty.

The end of the game was the beginning of a fresh drama over whether Brady will return. If the 42-year-old’s time with the Patriots is really over after 20 years of all-time greatness, the record will reflect that his final pass was an indignity, a pick-six deflected from his own end zone and into the hands of the Titans’ Logan Ryan. “Tough way to end it,” he said. Which may be a weird incentive. Afterward, Brady essentially put to rest the notion that he could retire, calling it “pretty unlikely.” But whether he plays for the Patriots is by no means assured.

He completed 20 of 37 passes for 209 yards and no touchdowns, a performance in keeping with a season in which he declined statistically, perhaps because he didn’t have as strong a supporting cast as in other years. His contract will expire March 18, and whether the Patriots and Coach Bill Belichick will make a large commitment to a 42-year-old who struggled to connect with young receivers remains to be seen. “Right now we just finished the game,” an all but inaudible Belichick said, refusing to address the issue.

Brady may want more money than they can offer. He may want a fresh start, with more weapons. He, too, was noncommittal. “Who knows what the future holds, I’ll leave it at that,” Brady said.

Only this much was certain: A long great run was over and it was a stale, painful ending. “No one needs to make choices at this point,” Brady said.

Brady and the Patriots have made winning such an expected outcome over two decades that we, and perhaps they themselves, became a little numb to it. Think about the physical and mental toll of reaching eight consecutive AFC Championship games and four of the last five Super Bowls, winning three of them. It was an insane rate of success in a sport that is brutal and constantly shifting, given free agency. In retrospect, it was unsustainable. They had to have a letdown eventually, and this was it. If nothing else, they had to be worn out from all that winning.

The mere fact that they were in the first round for the first time since 2009 suggested that the edge had come off the blade. The Patriots were unquestionably as vulnerable as they have been in years – losers of three of their last five games in the regular season. They were dealing with a unique and perhaps weighty peculiar emotional issue with a number of longtime veteran players – a close core group – set to become free agents along with Brady. Players like McCourty and special teams captain Matthew Slater.

So many things suggest the Patriots will be making sweeping changes in the offseason. Theirs was the oldest roster in the league, with an average age of 27. That wasn’t solely due to their 42-year-old quarterback, but also to tight end Ben Watson, 39, and an entire defensive unit with an average age of 29. There was bound to be turnover, “Probably because a lot of guys have been here and are older,” McCourty pointed out. “We’ve had a lot of guys stay here for a lot of years.”

For all of their gilded success, the aging Patriots felt like underdogs against the surging Titans, who had won seven of their last 10 regular-season games while averaging more than 30 points. The first half ended with a 14-13 margin for the Titans, but it established much more than that: It showed the Titans were simply more powerful.

Other than the neat sleight of hand from Brady to Julian Edelman that went for a 5-yard scoring run, the Patriots simply could not get into the end zone despite three long drives. Take the way they were stymied with a first-and-goal on the 1 late in the second quarter. It loomed ever larger as the game went on. So did the way the Titans replied, with an absolute punch in the mouth in the last two minutes of the half, with Henry chewing up whole sections of the field with his legs and accounting for 75 yards and a score, on his way to 182 rushing yards for the night.

What remained naggingly unclear was how much of the Patriots’ struggles were because of a decline by Brady and how much was because of other players. Was Brady’s occasional errancy, with a quarterback rating just 19th in the league at season’s end, the fault of an arm that doesn’t always do his bidding anymore and skittishness under pressure? Or was it because of young, unfamiliar receivers who didn’t always hit their marks? How much was on him, and how much on Belichick for failed roster choices? Those are sure to be part of their internal deliberations.

Still, Brady presided over a dozen wins this season, and he has a record of 36-13 since turning 40. He has been chronically unselfish and underpaid, signing team-friendly contracts in a quest to put great players around him. Can they reach such an accommodation again?

Regardless, the Patriots are inevitably approaching the end of something. “We’re all running out of time and chances with every year that goes by,” Brady said. It won’t be easy, whenever it finally happens, for the Patriots to transition from Brady’s well-educated patience, his will to win, and his scanning intelligence. The only thing that can be said for sure is that Brady and the Patriots have been a glorious partnership. “There’s nobody who’s had a better career, I would say, than me – being with them,” Brady said.