Xavier Tillman faces a crossroads season with Boston, needing to stay healthy and offer a real three-point threat to win a steady backup role behind the frontcourt. His defense remains elite on switches and in forcing turnovers, but his offensive game lacks a credible spacer or ball-handler, keeping him on the fringe when the Celtics rotate bigs.

With Horford, Kornet and Porzingis out of the mix, a clearer path should exist if Tillman can stay durable and develop a league-average jumper. This season may define whether he can become a functional two-way big or drift into limited backup minutes elsewhere.

Boston's 2025-26 roster pivots around health and versatility, with Jayson Tatum anchoring the offense and a deep, multi-position rotation ready to push pace and space. The ranking highlights a mix of seasoned shooters and young contributors vying for minutes behind the core, while Anfernee Simons arrives as a scoring boost from the Holiday swap. Development paths for Hauser, Pritchard, White and the wings shape a dynamic, high-floor lineup with upside down the roster.

Rookies like Hugo Gonzalez and Neemias Queta push for time, while vets such as Garza, Scheierman and Minott must prove their fit. The balance of defense, pace, and shooting will determine starter roles and key bench minutes, all within a Celtics team that aims to evolve under a new chapter of the Tatum-Brown era.