Celtics Excited About Xavier Tillman Defense as Trade Search Continues

BOSTON — New Celtics big man Xavier Tillman Sr. will arrive to a locker next to Jayson Tatum’s in the corner of Boston’s locker room this weekend. The one Lamar Stevens vacated on Wednesday.

The Celtics, expected to remain quiet at the trade deadline, got ahead of Thursday’s last-minute hustle and made an assertive offer for a player they clearly viewed as a missing piece in their championship pursuit. A potential defensive running mate alongside Tatum in the front court who can take pressure off other defenders if the Celtics find a consistent role for him.

Two future second-rounders and Stevens pried Tillman, long beloved in Memphis, away from the Grizzlies at 25-years-old ahead of his first free agency. Self-described as a family man, the Celtics more pertinently added more defense, versatility and reliable physicality in their front court. You can never have enough.

Despite the success and general availability Kristaps Porzingis and Al Horford achieved early this year, playoff inexperience marked Luke Kornet, Oshae Brissett and Neemias Queta’s records behind them. Boston could get by with that group in regular season scenarios. It became less clear whether that mix could win a playoff game, or series, in place of a short-term or longer absence by one of Boston’s main bigs, one carrying injury history and another age into the postseason. Tillman has impacted two playoff series early in his career.

“Toughness, he can pass, skilled,” Joe Mazzulla said after Wednesday’s win over the Hawks. “High IQ, obviously a good defender in pick-and-roll. Excited to have him and it’ll be important that he gets up to speed with our defensive schemes. I think he’ll give us some versatility.”

That last caveat, however, could lead to a ramp-up and trust-building period for the newest Celtic. While Brad Stevens admitted Boston could use some extra perimeter size, Mazzulla relayed confidence in the group the team already courted in the time leading up to the deadline. Still, in a critical year, Boston didn’t want to get left short-handed at a position and have that be the reason the team falls short of a championship.

Despite Mike Muscala, one year ago, arriving at a similar cost and rarely playing into the postseason, the Celtics lost both Robert Williams III and Grant Williams as big bench defenders and scorers.  Tillman brings the former, if not the latter, and while MassLive reported that Boston could pivot to a depth wing addition by 3 p.m., Jake Fischer indicated on Thursday morning that the Celtics are probably done. They maintain one open roster spot. It’s hard not to consider Tillman a hit now given the options available to Boston. Whether he plays a substantive role and stays with the Celtics long-term will decide how successful the move becomes.

For Kornet, his relevance will remain for some period of time due to the trust, experience and reliability he’s formed within a fast-paced system on both ends of the floor. The same goes for Brissett. Their versatility on defense falls far below Tillman’s though, and the new big man boasts a similar dribble-handoff, passing and post hook floater game to Kornet’s — only with finishing concerns around the rim. Nobody on the roster understands the difficulty of the transition, defensively, more than Porzingis.

“He’s gonna have his processor working,” he told CLNS Media. “It’s a lot of adjustments on the go, and Joe likes to just boom, we have to be ready to respond, whatever the coverage is, whatever changes, whatever the matchup is in that moment, boom, you have to be ready for it. I think he will pick it up and understand that it’s gonna be on the go. That’s a little bit different here and it challenges you as a player to respond quickly to whatever Joe sees. It might take him a little bit of time, but once he finds that ability to switch his mindset on things, he’ll be fine.”

The offensive numbers might arrive more glaring than any defensive acclimation concerns. Tillman shot 40.8% from the field through 34 games this year while playing over 60% of his minutes at center, according to Basketball Reference. That’s due in part to increasing the share of attempts he takes from three, 1.6 per game, to 25% of his total field goals. He only finished 22.6% from deep, reducing his career average to 26.4%. He’s also a 57.4% shooter at the free throw line who finished this season in Memphis ranking in the fourth percentile among rollers by generating only 0.67 points per possession. That number crept closer to league average at 1.15 PPP in 2022-23.

Playing next to Boston’s defense-bending offensive talent should open lanes to the rim, whether on cuts, rolls and only generated 0.8 put back opportunities this season per game, shooting 27.8% on them. That’s why Boston could acquire him for a low price at a $1.9-million salary point. If he lit it up offensively alongside his defensive skillset, he wouldn’t land on the Celtics. Come playoff time, defenses can stash a weak defensive guard on him or ignore him as he tries to space or roll, challenging his ability to stay on the floor. It’s most likely that Boston continues to lean on Porzingis and Horford for all of the team’s center minutes when healthy in the playoffs.

That allows Tillman to play the role that the Celtics could afford to utilize assets to bring him in for. If Julius Randle or Giannis Antetokounmpo stress their defense for a quarter, Tillman provides a physical, on-ball option against them similar to the one Grant once provided. He averaged 8.7 points, 8.0 rebounds and 3.2 assists per game in the Grizzlies’ series against the Lakers. Tillman guarded Anthony Davis after logging big minutes against Karl-Anthony Towns the previous year.

As a defender this season, only Isaiah Hartenstein and Jonathan Isaac ranked higher than Tillman’s +4.0 expected plus-minus. Opponents shot 44.1% against him on over 10 shots per game. A premium skill at a discount price, but a player that’ll force Mazzulla to adjust his rotation to find a consistent role for. Fortunately, both Horford and Porzingis can shoot at the four if the Celtics lean even further into double-big alignments.

“His ability to defend (excites me),” Porzingis said. “All kinds of multiple positions and he has some tools offensively that can help us. His build, he’s a really strong defender and he can guard multiple guys, which is gonna be a huge advantage for us.”