The 2025-26 VSiN NBA Betting Guide was released on Tuesday, October 7. The 79-page publication features best bets from our talented VSiN hosts and analysts, betting strategy advice from Jonathan Von Tobel and Kelley Bydlon, and trends/insights from Steve Makinen. The guide also features team-by-team previews for all 30 NBA teams, including one on the Boston Celtics. Keep reading to see how we think the Celtics will do compared to their regular season win total of 41.5.
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Offense
With just under three minutes left in Game 4 of Boston’s Eastern Conference Semifinal against New York, Jayson Tatum tore his Achilles. The Knicks were already up nine in that game and ahead 2-1 in the series, so don’t let anyone tell you the injury cost Boston the series. But it will likely cost the Celtics the entire 2025-26 season.
Tatum is one of the best players in the world. The 27-year-old has been the centerpiece of a Boston offense that’s finished top-five in adjusted offensive rating in four straight years — including setting the all-time mark in 2023-24 (122.0).
Last season, Tatum averaged 26.8 points, 8.7 rebounds, and 6.0 assists. He’s shown he can score 30+ per game when needed, posting 30.1 per night in 2022-23. He also does it efficiently, ranking eighth in Estimated Plus-Minus (+4.2) last season. Step-backs, side-steps, downhill drives — he scores every which way, all while staying within the flow of the offense.
Replacing a five-time All-NBA player is impossible, and the Celtics didn’t make it any easier by trading Jrue Holiday and Kristaps Porzingis, and letting Al Horford walk. All three were critical to Boston’s recent dominance.
That leaves Jaylen Brown as the new No. 1 option. He battled through injuries last year, but he’s only a few seasons removed from averaging 26.6 points. Brown has the tools: a clean jumper, mid-post scoring, elite athleticism, and a knack for cutting and running the floor. But his shaky handle has always made him a little more of a Robin than a Batman.
Derrick White and Anfernee Simons will have to carry big loads, too. White has become one of the league’s top shooters, taking 9.1 threes per game last season while still hitting 38.4%. His efficiency may dip with more volume, but he’ll scale up just fine. Simons, meanwhile, gets a fresh start after averaging 19.3 points in Portland on 36.3% shooting from deep. He fits the Celtics’ three-point-heavy philosophy and should thrive with better spacing and structure.
Boston can also rely on Payton Pritchard and Sam Hauser. One — or both — of them could even step into a starting role. Pritchard is a flamethrower off the dribble who can sneak in some drives. Hauser is a lights-out catch-and-shoot weapon who stretches defenses to their limits.
One thing is certain: Joe Mazzulla’s Celtics will keep firing from deep. Last year they attempted 48.2 threes per game, the most in NBA history. Golden State shot the second-most threes last year, but the Warriors took nearly six fewer per game. “Mazzullaball” has been wildly effective since he took over, and he won’t slow down now, even if the loss of stretch bigs makes it trickier.
The real concerns are the center spot and overall depth. Relying on Neemias Queta, Chris Boucher, and Luka Garza to man the five is dicey, and the overall rotation feels thinner than it has in years. Mazzulla will need unexpected contributions from somewhere to keep Boston afloat. He’ll also need Brown to play 70+ games. This team isn’t talented enough to win without him.
Defense
Losing Tatum hurts on both ends. He’s long been a steady wing defender. Trading Holiday — one of the best point-of-attack defenders in the league — for Simons, who has been poor defensively, only compounds the problem. Add in the departures of Porzingis, Horford, and even Luke Kornet (an underrated rim deterrent and creator of the “Kornet Contest”), and Boston has shed a ton of defensive toughness and versatility.
The Celtics will be smaller and more vulnerable. White remains an excellent guard defender, and Brown can handle most wing assignments, while Queta and Boucher offer more on this end than they do offensively. But expecting another top-10 defense — something Boston has achieved in four straight seasons — is unrealistic. Dunks & Threes projects them to fall outside the top 20.
If there’s a silver lining, it’s Mazzulla’s system. Boston has excelled at transition defense and three-point contests, holding opponents to 34.7% from deep last year (third-best in the NBA). If Mazzulla can drill the same principles into the new rotation, the Celtics might at least scrape by with a respectable defense.
Outlook
It feels strange to talk about the Celtics as anything but contenders, but that’s the reality: without Tatum and with so much roster turnover, Boston could struggle to reach .500 and they aren’t a lock to make the playoffs — even in a weak East.
The dream scenario would be overachieving, sneaking into the postseason, and then welcoming back Tatum for a surprise run. Early reports suggest he’s recovering quickly, but the team is unlikely to rush him.
The likelier outcome is Boston taking its lumps in 2025-26, regrouping, and aiming to reload around a healthy Tatum next summer. The window isn’t closed, but it’s a little fogged up.
Prediction: Under 41.5 Wins
