Mitchell Robinson leaves Knicks for Celtics in NBA free agency gut-punch

The inevitable became reality. The champions will not fully be running it back. Mitchell Robinson is not returning to the Knicks, as he intends to sign a three-year, $47.4 million contract with the Celtics in free agency, according to ESPN.Previously the longest-tenured Knicks player, it puts an end to his eight-year tenure with the team, which ended in a title. A second-round pick, Robinson – now 28 – developed from a raw shot-blocker into a key bench piece and one of the best rebounders in the NBA. Despite his importance, it became clear that the Knicks would not be able to make a respectable offer while maintaining owner James Dolan’s stated goal of staying under the second apron. The Knicks already secured two of their top three free agents in Jose Alvarado and Landry Shamet to multiyear deals along with Mohamed Diawara.

Those moves left the Knicks roughly $9 million under the second apron and still needing to sign three players heading into Tuesday’s start of free agency. Teams were officially allowed to begin negotiating with all other free agents (they can negotiate with their own free agents immediately after the Finals) on Tuesday, though no deals can be made official until July 6. That trio of moves meant the Knicks could really only fill out the roster with minimum deals, way below what Robinson commanded on the open market. Really, once Dolan expressed his desire to stay under the second apron, it was expected that it meant bringing back Robinson would not be possible.The Post’s Stefan Bondy reported last week that it was unlikely he’d be back. His absence means the Knicks now need a backup center behind Karl-Anthony Towns. And his departure means Miles McBride – who arrived in the 2021-22 season – is now the longest-tenured Knick. Robinson’s final contribution was securing one of the biggest rebounds in franchise history – corralling Josh Hart’s missed free throw with 26.1 seconds left and the Knicks up by three points...