Sam Cassell checks every box as ideal hire for Celtics

​After rookie head coach Joe Mazzulla and the Boston Celtics fell short of their stated goal of getting back to the NBA Finals, president of basketball operations Brad Stevens pledged to add an assistant coach to Mazzulla’s staff with "significant NBA experience."

Stevens delivered the Celtics an experience infusion with the addition of 2008 champion Sam Cassell.

The 53-year-old Cassell has three decades of NBA experience, winning three titles in a 15-year NBA career, then spending the last decade and a half as a lead NBA assistant, the majority under former Celtics coach Doc Rivers.

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Mazzulla had a staff thin on NBA experience, particularly after Damon Stoudamire departed in March to take over as head coach at Georgia Tech. Stevens noted the team considered experienced assistants after Mazzulla elevated from behind-the-bench assistant to head coach following Ime Udoka's suspension in September. But Boston instead rode out the season with its in-house assistants.

Cassell’s addition could be just the start of reshaping Mazzulla’s staff, with Udoka hinting recently that he’s hopeful to bring aboard some of his former assistants now that Boston’s season is over.

Stevens stressed that his job is making sure Mazzulla has a staff that feels comfortable sharing ideas and making them a reality.

"I do think the biggest part of a staff is having a group of people that work well together, that can throw great ideas against the wall and then agree on the path ahead and move forward with what the decision is that's made," Stevens told NBC Sports Boston last week.

"I did think that, obviously, when we had our coaching situation in September, we tried and looked at a couple of people. To get somebody to move at the start of a school year, [someone] who likely has a family or whatever, or in the middle of the year, is a little bit more challenging, right? And then the reality is that not a lot of people are available at those times.

"But we will try to make sure that we add one person to our bench with significant NBA experience, and then go from there."

Cassell checks every possible box for what the Celtics should covet in a top assistant next to Mazzulla. That includes …

NBA playing experience

A first-round pick in the 1993 NBA Draft, Cassell won three titles while playing 15 seasons for eight different teams. Cassell was a one-time All-Star, earning the nod as a 34-year-old in Minnesota during the 2003-04 season, the same year he landed an All-NBA berth.

Paul Pierce went so far as to suggest that it was Cassell, signed as a buyout player in March of Boston’s 2008 title run, that really served as a Big Three member with him and Kevin Garnett on that title team.

NBA coaching experience

Cassell has spent the past 14 years as an NBA assistant, and that doesn’t include the 2008-09 post-grad-type year he spent with the Celtics before his playing career was officially over. Cassell spent five seasons with the Wizards, six years with the Clippers, and the last three seasons with the Sixers.

Coaching star players

The biggest chunk of Cassell’s coaching career included six seasons as an assistant with the Clippers, the tail end of which featured a team helmed by two All-Star wings in Kawhi Leonard and Paul George. Cassell also spent time working with former MVP James Harden and current MVP Joel Embiid during his time with the Sixers.

A familiarity with Boston

Cassell played in more playoff games here (21) than regular-season games (17) in 2008. Even in the twilight of his career, Cassell was known for his penchant for big plays in big spots (and his basketball-lugging celebration that often came out in those spots).

Here’s what should excite Celtics fans most: Garnett has routinely credited Cassell with bringing out the best in him during their time together in Minnesota in the early 2000s. In a recent Showtime documentary, Garnett noted, "If you know Sam, you know that he is the type that will bully his personality on top of you."

The Celtics need a former NBA star who isn’t afraid to mold (and scold) the likes of superstars Jayson Tatum and Jaylen Brown. Maybe Boston’s stars can absorb some of Cassell’s late-game bravado by being around him and alleviate some of their crunch-time woes.

Cassell has been patiently waiting his opportunity to ascend to a head coaching job. He has a chance to bolster his resume in Boston and showcase his leadership abilities as part of Mazzulla’s new-look staff.

His arrival immediately boosts Boston’s staff from one with virtually no NBA experience, to one with a coach that has been through a whole bunch of big moments over the last 30 years.