Any doubts about Tiago Splitter's bona fides as a defensive player were erased in the playoffs last season. Splitter guarded Dirk Nowitzki and LaMarcus Aldridge, two of the game's most potent scorers, as well as anyone could. But while the accolades for his man-to-man defense have been plentiful since then, he's still underrated in his impact as a team defender and rim protector. Tiago is as integral to the Spurs' defensive success as anyone on the roster. And that's become patently clear this season in the two games he's missed so far with calf and back injuries.
The Spurs start two defensive anchors
A little known fact about last regular season is the Spurs were better on defense with Splitter in and Duncan out than the other way around. With just Splitter and not Duncan in the Spurs allowed a lower field goal percentage, fewer points per possession and a lower field goal percentage at the rim. And thanks to the new SportsVU data the NBA has made available, we know that with Splitter defending within six feet of the bucket opponents shot 47.3%, 12.5 percentage points worse than they averaged from that distance during the season. Both of those numbers are better than Duncan's. Splitter clearly can provide a defensive presence on his own.
This is not an indictment on Big Fun, who remains one of the best defenders in the league and was better than Splitter in the playoffs. In fact so far this season Duncan has stepped up and made up for the loss of Splitter by anchoring any unit he's been a part off, like he had in the past. With Duncan on the court the Spurs are allowing just 94.9 points per 100 possessions and an opponent field goal percentage of 38.7%. Both those numbers are fantastic, as is the rim protection Duncan is providing. Timmy is more than doing his part. The problem for the Spurs on defense comes when he sits.
Bad D abounds on the bench
With Duncan off the court, the percentage the Spurs allow at the rim goes from an impressive 50% to an outrageously high 69.2%. Obviously the sample size is small. But it lines up perfectly with what we've seen on the court the last two seasons. Outside of Splitter and Duncan, the Spurs have no bigs that can provide even a semblance of rim protection.
Aron Baynes has been getting the nod over Jeff Ayres when Duncan sits , which makes sense considering the strides he's made on his short NBA career. But he's simply not equipped to anchor a defense. Baynes is a great rebounder and a stout post defender. But he's too slow and doesn't have the intuitive understanding of space that Duncan and Splitter have. As a result, he's often late on rotations, as he was on these two Devin Harris drives:
Or he makes incredible mistakes.
Baynes is supposed to double team Dragic to get the ball out of his hands but doesn't do it until Len is ready to set the screen. As a result he doesn't accomplish the task and is out of the play once Dragic drives.
And here we see Baynes staying way too close to Len instead of dropping back, like the Spurs' centers are supposed to on the pick-and-roll. Green just ignores the pick because he has an open straight line drive to the basket.
The awareness just isn't there and that's not something we can expect a 28-year-old to improve on drastically. More reps will definitely help. But it seems like Baynes is not destined to be a defensive anchor. The same applies to Jeff Ayres, who has a slight edge on quickness and discipline over Baynes but doesn't truly make enough of a difference in the defensive end to make up for his serious offensive limitations.
Yet one of them will have to give the Spurs some quality defensive play because knowing Pop's philosophy on minutes management, Duncan is not going to play more. And the Spurs can't afford to suffer such a precipitous decline when he sits if they hope to win against good offensive teams like the Hawks, Rockets, Clippers and Warriors, which are four of their next five opponents. If the back up bigs don't step up, things could get ugly for San Antonio early in the season.
Is there an easy fix?
It doesn't appear like there is, no. Pop could try to change the substitution patterns so that Duncan checks out earlier and Baynes shares the floor with Green and Leonard, who provide better containment defense in the perimeter than Ginobili and Belinelli. But it would disrupt the chemistry of both the starters and the second unit. Subbing Baynes out when he makes mistakes, like Pop did against the Suns, makes sense but it's not like Jeff Ayres is much better.
The Spurs simply need Splitter back. That's the only way they can get their defense back to top five level. Fortunately, he should be close to returning now, as he has been nursing the calf injury for over a month and the mysterious back ailment doesn't sound too serious.The bad news is it will likely take Splitter some time to get back in playing shape. So Baynes or Ayres will probably get minutes even with Splitter back, but hopefully in smaller, more suiting roles.
For now, the Spurs will have to weather the storm and try to get some Ws any way they can.
Get well soon, Tiago.