The Boston Celtics opened the 2022-23 NBA season with three consecutive victories.

Once the competition increased, though, so did the loss column.

They're 1-3 in the four games since, dropping one game to the Chicago Bulls and two of them—both in overtime—against the Cleveland Cavaliers.

This is mostly fine, and not in the drinking-coffee-inside-of-a-burning-room meme kind of way. Boston's biggest ambitions for next June won't be decided in November, anyway.

Still, this squad has delivered a few surprises along the way, and we're breaking down the biggest ones here.

Jayson Tatum Making A(nother) Leap

Of all the twists and turns this campaign could have taken, it's hard to imagine anyone saw Jayson Tatum forcing his way into the Most Improved Player race.

Now, the 24-year-old almost certainly won't capture the hardware, since he's already a household name. Still, none of his previous seasons—not even the last two, which included two All-Star Game starts and an All-NBA first-team honor—have been this dominant.

After averaging 26-and-change points the past two seasons, he has suddenly rocketed up to 30.1. And he's not dominating the basketball to do it; in fact, his 30.7 usage percentage and 19.4 field-goal attempts per game are both his lowest in three seasons, per Basketball-Reference.

Tatum is simply powering this improvement with some of the best shot-making in the business. His 52.9 field-goal percentage and 91.8 free-throw percentage are both personal bests by wide margins, and they've allowed his true shooting percentage to spike to 67.0, towering above his previous high of 58.6.

A Steep Defensive Decline

To say the Celtics had last season's best defense would be accurate but also an understatement.

Once they flipped the switch in late January, they started running circles around the rest of the league. From Jan. 29 to the campaign's close, the Shamrocks surrendered just 105.9 points per 100 possessions, per NBA.com. The next-best team, the Miami Heat, gave up 109.6. The statistical gap between them was the same size as the one separating Miami from the 14th-ranked Minnesota Timberwolves.

This was basketball mastery—if not basketball sorcery—and with so many of the same stoppers still in place, including reigning Defensive Player of the Year Marcus Smart, you might think Boston is busy obliterating offenses again.

That isn't close to being the case, though. Instead, the Celtics have tumbled all the way to 19th in the category, a slide too steep to be entirely attributed to the absence of Robert Williams III (knee surgery).

It might be a case of skewed stats in a miniature sample, it might reflect Williams' importance, or it could be a combination of both items and more, but no one expected Boston to struggle on that end to this degree.

Boston's Perimeter Surge

Last season's Celtics weren't a bad shooting team, but they weren't great. They finished the season eighth in average threes per game (13.2) and 14th in accuracy (35.6 percent).

That surely fueled their offseason decisions to add Malcolm Brogdon and Danilo Gallinari, both 37-plus-percent career shooters. With Gallinari lost to a torn ACL, though, and Brogdon perhaps handling a smaller role than expected (23.1 minutes per night, seventh on the team), Boston is probably seeing similar results from range, right?

Well, this slide wouldn't be written if that was the case.

The Celtics have splashed a season-high 15.4 threes per game and converted their long-range looks at a 38 percent clip (eighth overall).

Among their rotation regulars, only Jaylen Brown and Marcus Smart are shooting below 37 percent from three. Grant Williams and Sam Hauser are both cashing in better than half of their outside shots, while Derrick White has found his mark 42.3 percent of the time.