Who should start when Knicks are fully healthy: Isaiah Hartenstein or Mitchell Robinson?

As Knicks fans eagerly await the return of three of their team’s key starters -- OG Anunoby, Julius Randle and Mitchell Robinson -- from injury, the coaching staff is planning on how best to implement them back in the lineup. The goal being to use the last month of the season to ramp them up to 100 percent and find some chemistry in time for a playoff push.

That won’t happen without making some tough choices though. For example, at full strength should the Knicks start Robinson or Isaiah Hartenstein at center?

Robinson is likely the higher impact player, an elite defender and offensive rebounder that provides a verticality other members of the roster don’t. But it was Hartenstein that anchored New York’s devastating starting five post-OG trade, and provides much more optionality offensively.

Let’s go through each case and see who would be a better fit in the opening unit.

The case for Mitchell Robinson

Robinson hurt his ankle 21 games into the season, mere weeks before the Knicks shook up their roster by trading RJ Barrett and Immanuel Quickley for Anunoby. He played the best basketball of his career during that stretch, anchoring a top-10 Knicks defense behind a more mature and predictive approach you’d expect from an NBA veteran.

Robinson only averaged 6.2 points, but fully committed to his role as the team’s defensive ace and rebounding menace. At the time of injury he had an offensive rebounding rate of 20.2, meaning one of every five Knick misses ended up in his hands, which would lead the league today and only be matched by three other players since 1974.

Defensively, Robinson was more reminiscent of peak Tyson Chandler than the bouncy block-chaser he joined the Knicks as. His blocks per 100 possessions are at a career-low 2.2, but that’s more a feature than a bug, a symptom of not flying out of position and instead patiently waiting for offensive players to drive into his trap.

You’ll find evidence of that in his fouls per 100 possessions, at a career-low 3.3 after struggling with them for most of his career. That’s allowed him to notch a career high 29.2 minutes per game, making a better impact for longer.

He’s utilized his length in new ways, actively pressuring passing lanes, especially in the pick-and-roll. That’s resulted in a career-high 2.6 steals per 100 possessions, allowing him to kill opposing possessions without being out of position.

Hartenstein’s a very strong defender in his own right, also up there in offensive rebounding leaders, but the upside is all Robinson’s. His athleticism and length can’t be taught, and he was finally channeling that through advanced defensive reads before going down.

Coming off this injury, Robinson will likely have some rust having not played NBA basketball in four months, missing over 40 games -- or half the season. If he can quickly shake that off though, he should have the benefit of being fresher than Hartenstein and any opposing starting center that’s had to grind through this full campaign.

The other argument for Robinson starting is Hartenstein is a better fit for the bench. Lineups with Brunson and Randle should be fine from an offensive standpoint, and likely need maximized role players doing the dirty work more than anything.

However, the reserves will likely only be paired with one of those guys at a time and will need more optionality offensively to create good looks. Hartenstein’s passing might make a little more sense utilized there than in the starting lineup.

We’re likely going to end up seeing both utilized at different times as head coach Tom Thibodeau experiments to find the ideal five to take into the playoffs. We’ve yet to see what kind of defensive juggernaut a lineup that includes Anunoby and Robinson looks like, and if it’s as scary as it looks on paper, it might be hard to move away from.

The case for Isaiah Hartenstein

Where Robinson has the defensive upside, Hartenstein boasts the offensive edge. He’s a great passer from the five spot, able to comfortably play out of the high post, and has better touch on his dribble and inside shots than Robinson.

Hartenstein’s scoring 1.20 points per play on his post-up attempts, a solid mark on few attempts. The Knicks won’t be going to that often, but having the option when the moment calls upon it never hurts, especially in the postseason.

Speaking of the playoffs, the last two times the Knicks made them, their defense held up fine but their offense sputtered. Spacing and stagnation were problematic, and Hartenstein helps with both.

He’s also had a good month of basketball with the new starting five, building some real chemistry in their 14-2 record in the month of January. Maybe it’s only a month, but the Knicks will only have that amount of time to get guys back in rhythm and playing together smoothly which is no easy task.

That head start could give Hartenstein the advantage; he won’t be trying to shake off rust like Robinson. On the flip side, he’s played most of this season, and the wear is starting to show with recent Achilles flare ups and a slight regression in his performance.

Robinson returning and Precious Achiuwa emerging as a rotation piece should help limit his minutes in this final stretch, ideally leaving him fresh enough for the postseason. When he’s 100 percent, he may not have Robinson’s freakish stature, but he is still a force at the rim defensively.

Verdict

There may not be a right and wrong answer here, as basketball is a game of endless variables, and this decision could come down to something as simple as playoff matchup.

If the Knicks reunite with the Cleveland Cavaliers and Robinson looks decent, best believe Thibodeau will run with him after last year’s destruction of their vaunted frontcourt. Against Boston, they may want a better perimeter option against Kristaps Porzingis going the other way.

Thankfully, this is a great problem for the Knicks to have. If too many choices are their biggest concern entering the postseason, they’re in great shape. Still, the wrong one can end the season prematurely, so expect a trial-and-error process as the lineup comes to full form in these final weeks.