GREENBURGH, N.Y.—The banners hanging from the rafters here at the Knicks’ Greenburgh training facility betray a franchise with a rich but rocky history. Only two championship banners hang among nine retired jerseys, the last from the 1972-73 season.

Phil Jackson was on that Knicks championship team. Now, 42 years later, he has returned as the team’s president with a mandate from owner James Dolan to add another banner to the collection.

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