Coming into the 2025-26 season, there was no bigger storyline than what the Boston Celtics (8-7) would look like without Jayson Tatum.

After tearing his Achilles in the fourth quarter of Game 4 of the Eastern Conference Semifinals against the Knicks, the five-time All-NBA forward underwent surgery to repair the tendon within 24 hours. And while that incredibly fast turnaround time could mean a fast recovery for the 27-year-old, it doesn’t guarantee a return for this season.

For all intents and purposes, there should be no real expectation of Tatum returning to the basketball court until the fall of 2026.

With Tatum out, the path has been cleared for fellow All-NBA talent Jaylen Brown to show he has what it takes to be a true No. 1 option for a team with enough talent to compete towards the top of a wide-open Eastern Conference.

He’s already won both an Eastern Conference Finals MVP and Finals MVP - we know the guy can ball. But never in his career has he been asked to be the guy to elevate everyone else around him. Never has Brown been asked to be the solo maestro of the orchestra. This season is a true test of his abilities to be a real face-of-the-franchise type of player. Can he be a Batman, or is he destined to be an overqualified Robin?

Through 15 games, it’s been a mixed bag.

While his individual stats have been fantastic, ranking 12th in the league in points per game (27.5) while averaging 5.5 rebounds and 4.1 assists, the team has not been able to find consistent winning almost 20% of the way through the season.

Yes, I know they’re in the midst of a three-game win streak. But if you watched each of their last two games, either one very easily could have swung in the exact opposite direction. 8-7 could very easily be 6-9, which feels a whole lot different than one game over .500 (save the 69 jokes, guys).

Even before they rolled the balls out, I had predicted the first month of the regular season to be a gauntlet for this team. In my preseason blink test column, I had them at 9-6 through 15 games - not setting the world on fire by any means as they battled through a tough slate to open the season. I still feel secure in my 43-39 prediction, but I’m certainly less confident than I was before opening night when you’re allowing 21 points off 20 turnovers to a two-win Nets team (2-12).

And don’t look now, but that gauntlet ramps back up right after their NBA Cup game with the Nets on Friday:

- 11/23 vs. Orlando (8-7)

- 11/26 vs. Detroit (13-2)

- 11/29 @ Minnesota (9-5)

- 11/30 @ Cleveland (10-5)

As I’ve written here before - the true mark of a No. 1 in the NBA is being able to elevate the guys around you. And while guys like Payton Pritchard and Derrick White are starting to play better, it hasn’t been enough for anyone who follows this team to feel confident in Boston making any sort of playoff push in April.

Heck, you’ve got Celtics super-fan Bill Simmons on his latest podcast talking about having this team trade Anfernee Simons and tank for next summer’s NBA Draft. When Simmons is out on the operation, you know something ain’t right.

Even with his scoring, Brown admits he’s not playing as great as he should be. Here’s what he has said the last two games:

Tom Carroll (@yaboiTCfresh) on X While recording his first double-double of the season (33 points, 13 rebounds), Jaylen Brown said postgame that he didn’t think he had a good game: “My team counts on me to play a little bit better, and tonight I didn’t really play that well. So, looking forward to the next two

Noa Dalzell 🏀 (@NoaDalzell) on X Jaylen Brown was candid about his limited first-half minutes: “I was just playing like shit in the first half.”

Whatever the case may be, the Brown-led Celtics are not performing close to the level of the Tatum-led Celtics. And to be fair to Brown, he doesn’t have key supporting cast members Al Horford, Kristaps Porzingis, Jrue Holiday and Luke Kornet. I think we all need to do a better job of reminding ourselves of that as the season trucks along. Brown’s job is more difficult than Tatum’s ever was. This is the most roster turnover Boston has had in a long time, and they’re still feeling those growing pains early.

15-Game Progress Report Grade: B-

Tom Carroll is a contributor for Roundtable, with boots-on-the-ground coverage of all things Boston sports. He's a senior digital content producer for WEEI.com, and a native of Lincoln, RI.