The biggest questions for Boston’s bank

After introducing the Celtics’ rookies in Part 1 of our 2024-25 roster preview and the reserve players and roster hopefuls in Part 2, let’s take a closer look at the reserve players who should be part of head coach Joe Mazzulla’s core rotation this season.

Al Horford

The ageless Horford accepted a demotion to sixth man last season after Boston signed Jrue Holiday and Kristaps Porzingis, coming off the bench for the first time in his 17-year NBA career. That will be the case again when the Celtics are at their best – but that won’t be the case for at least the first month of the 2024-25 season.

Porzingis underwent leg surgery this offseason that will keep him out of action until at least Thanksgiving, meaning Horford should begin the season as Boston’s starting center. How Mazzulla manages him, however, will be a key storyline to watch.

Horford’s workload after Porzingis’ injury (15 consecutive starts and 30.3 minutes per game) is unsustainable for a 38-year-old – even someone as focused on his fitness as Boston’s beloved big man. Horford averaged 26.8 minutes per game last season and has missed the second-most back-to-back games since returning to the C’s in 2021.

Look for Mazzulla to rotate one or more of Boston’s other big reserves (more on that later) into the starting lineup while Porzingis recovers.

Sam Hauser

When the Celtics selected high-scoring wing Baylor Scheierman in the first round this summer, it raised questions about whether the team viewed him as a replacement for Hauser. Those questions were quickly answered when Boston picked up Hauser’s contract option two days after the draft and signed him to a four-year extension a month later.

The $45 million deal represented a huge raise for Hauser, who went undrafted in 2021 and had to prove himself in the G League before becoming one of the best backups on a championship team. The 26-year-old was one of the NBA’s best 3-point shooters last season – his 42.4% shooting percentage was seventh-best among 73 players who attempted at least five threes per game – and has improved tremendously as a defender, best seen in his possessions against Luka Doncic in the NBA Finals.