Why the slumping Celtics no longer look like the league's best team

BOSTON – Remember November? When the Celtics were the NBA’s feel-good story, surging through a grimace-worthy (and likely) season-ending injury to Gordon Hayward to rattle off 16 straight wins and start the season 22-4? That team beat San Antonio, upended Golden State and looked like a legitimate threat to LeBron James’ Eastern Conference supremacy.

Then came December, a defensive collapse and a return to the kind of mediocrity many feared when Hayward went down. Boston’s 111-103 Christmas Day loss to Washington was a familiar story — poor defense, horrendous rebounding and an offense overly reliant on the brilliance of Kyrie Irving to put points on the board.

What’s happened? Let’s start with what’s easy: The schedule has been brutal. Boston was tabbed for the NBA’s annual London game this year, and the schedule-makers — at the Celtics’ behest — gave the team four days off before and after. The fallout has been a compressed, pre-London schedule that has had Boston playing more games (37) at this point than any team in the league.

Big deal? Boston doesn’t think so. “Everyone is tired in the league,” coach Brad Stevens said. “Everybody has 82 games. We’ve had plenty of rest.” Still, it’s hard to ignore the evidence. Entering the game against the Wizards, Boston had played 150 more minutes than Washington. The vaunted Celtics defense — No. 1 in the NBA through its first 26 games — has fallen to 18th in its last 10. Turnovers are up. Rebounding has cratered.

“There’s not much difference, I just think you go through ups and downs in a season,” center Al Horford said. “We are still the same team. I actually think that we are better.”

Fatigue is only one factor in a packed schedule. Practice time is limited. Mistakes that young players make — and Boston hands big minutes to a few of them — are cleaned up in walk-throughs and film sessions instead of on the practice court. It matters.

There’s more, though. Depth was a concern in the aftermath of Hayward’s injury. It’s a bigger one now. Boston’s bench has been at best streaky and at worst anemic. Marcus Smart’s perimeter shooting has run hot and cold. Terry Rozier’s, too. Stevens has had to shuffle starters in with the second unit, as he did during Boston’s narrow win over Memphis earlier this month.

It’s a problem Boston is all too aware of. Some of it will be resolved with health. Marcus Morris made his return to the lineup on Monday after a nine-game absence because of a knee injury, and his versatility on both ends of the floor has been invaluable. But the Celtics remain among the NBA’s most active teams on the trade market, with an $8.4 million Disabled Player Exception available to absorb a contract or two. Boston’s pursuit of Anthony Davis has become the NBA’s most open secret, but it’s potentially available reserves such as Lou Williams and Tyreke Evans who could more realistically move the needle.

And let’s be real here: Boston was playing with fire early in the season, and often got away with it. Monday marked the 15th time this season the Celtics had fallen behind by 11-plus points. Boston’s record in the previous 14? 7-7. They had a miracle comeback in Oklahoma City, stormed back from 17 down to beat Golden State and erased a 16-point deficit in Atlanta. There are only so many holes you can dig yourself out of.

So would the real Boston please stand up? Chances are, in January, it will. The London trip will provide much needed rest, and Jayson Tatum gets better by the game. At 19, Tatum’s poise has been remarkable, and it was his 3-point shooting (again) that nearly powered Boston to another comeback win.

“It’s amazing to see his growth,” said Wizards guard Bradley Beal, whose friendship with Tatum dates back to their days in St. Louis. “It’s amazing to see him do it on this level. He’s a special talent. … Sometimes he’s a little too cool. Sometimes he needs to be a straight-up killer and take over some games. But it will definitely come for him.”

The East is a weird place right now. The Cavs — Monday’s loss in Oakland notwithstanding — have been hot, but James has been forced to work harder, earlier than in years past and we still have no idea what Isaiah Thomas is going to look like when he comes back. Toronto is officially the conference leader, but can the Raptors — even with a new-look offense — be trusted in the postseason. Will Milwaukee get a boost from Jabari Parker? Will Washington, finally injury-free, put together a run?

Strange days, indeed. Cleveland is more vulnerable than it has been since LeBron returned, but Boston will need to rediscover its defensive identity to knock off the Cavs — or any of the conference contenders for that matter. The dog days of the season have come early for the Celtics. A young team must figure out how to shake them off.

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