The Boston Celtics are now one of the deepest and most talented NBA teams. Last season, they lost to the Cleveland Cavaliers in the Eastern Conference Finals in seven games, but that was far from a disappointment. They exceeded expectations last year with their deep playoff run.
Even without major free agent signing Gordon Hayward for essentially the whole season due to a broken left leg, and stud point guard Kyrie Irving had left knee surgery before the postseason. Along with that, another injury that was felt in the playoffs was the loss of big Daniel Theis. He tore his meniscus in March and decided to have it further repaired. Theis had a very productive rookie season for the Boston bench.
He averaged 5.3 points, 4.3 rebounds and 0.8 blocks in 14.9 minutes per game. According to Gary Washburn of The Boston Globe, Theis’ team-friendly $1.378 million contract (per Spotrac) is guaranteed next season. That’s a smart move.
Although he’s not a household name such as some other Celtics in Irving, Hayward, Jaylen Brown or Jayson Tatum, the 26-year old provides Boston valuable big versatility. Where Theis really excels is at the defensive end of the floor. At 6’9″, and 243 pounds, he is really agile and can switch pick-and-rolls pretty well.
He plays with a good base, mirrors ball-handlers admirably, and has great shot-blocking instincts at the rim. Per 36 minutes, Theis had 1.8 blocks, according to Basketball-Reference. Even if he’s beaten slightly off the bounce, his timing and savvy allow him to recover consistently or get out to shooters. He placed in the 81st percentile in isolation and 92nd when defending spot-ups, per Synergy Sports Technology.
This kind of ability allows Boston to be more matchup-sound in their coverages. Players such as Irving and Rozier are not singled out as much with Theis’ rim protection behind them. Aron Baynes is a solid interior defender in his own right but does not have the rejecting presence Theis has. When facing the Giannis Antetokounmpo’s of the world, it would pay dividends for the Celtics to have him in there. A defensive box plus-minus of 3.4 (per Basketball-Reference), is nothing to sneeze at.
Factoring in impact defenders in Marcus Smart, Hayward, Brown and Tatum on the perimeter, Boston’s defense in lineups with Theis could be even more smothering. They had the best defensive rating in the NBA last season and were more stifling with Theis in the rotation. With the Boston Celtics being able to play Theis or Al Horford at the 4 or 5, it enables the C’s to be uber-versatile.
If teams attack Irving or Rozier constantly and just hammer the mismatch, it takes an offense out of rhythm. Over the course of games, that prevents opponents from playing at a faster pace and makes them predictable.
On the offensive end, Daniel Theis’ impact is also considerable as a roller and floor spacer for the Celtics. On the surface, his perimeter shooting isn’t outstanding, as he shot just 31.0 percent from three. However, there is reason for optimism. On spot-ups, he had an effective field goal percentage of 54.9 on a 16.0 percent frequency, per Synergy. That placed him in the 65th percentile. In the corner, he shot 53.3 percent, per Basketball-Reference.
With Hayward and especially Horford’s secondary playmaking ability, Theis should find ample opportunities to fire away from the corner this season. I would expect him to have a higher frequency than 25.9 percent of his threes being from there in 2018-19.
In addition to simply spotting up, he makes quality plays as a roll man for the Celtics, as was previously noted. Theis sets on and off-ball screens with good technique on the perimeter, which causes defensive hesitation. From there, that enables the Celtics to get mismatches or get open looks off defensive rotational confusion. Baynes does this well, too, but he’s not the pick-and-pop threat or passer Theis is.
Along with that willingness to shoot it against opposing rim protectors uncomfortable outside, Theis is a quality lob threat and diving threat as a cutter. He times his cuts really well in relation to penetration and finishes with authority. With a frequency of 15.7 percent, Daniel Theis placed in the 93rd percentile as a cutter for the Boston Celtics, per Synergy.
Lastly, Theis runs the floor better than Baynes and is a way better finisher. He is a solid offensive rebounder and could project well as a trailer for perimeter shots. Overall, head coach Brad Stevens and the Boston Celtics have a quality two-way chess piece brewing in Daniel Theis.