Boston Celtics signing key member of New York Knicks’ championship team

New York Knicks v Orlando Magic ORLANDO, FL - NOVEMBER 22: Mitchell Robinson #23 of the New York Knicks fight for position of a rebound against Desmond Bane #3 of the Orlando Magic during the first half of the game at the Kia Center on November 22, 2025 in Orlando, Florida. The Magic defeated The Knicks 133 to 121. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and or using this photograph, User is consenting to the terms and conditions of the Getty Images License Agreement. (Photo by Don Juan Moore/Getty Images) (Don Juan Moore/Getty Images)

New York Knicks v Philadelphia 76ers - Game Six PHILADELPHIA, PENNSYLVANIA - MAY 02: Mitchell Robinson #23 of the New York Knicks dunks against the Philadelphia 76ers during the fourth quarter of game six of the Eastern Conference First Round Playoffs at the Wells Fargo Center on May 02, 2024 in Philadelphia, Pennsylvania. (Photo by Tim Nwachukwu/Getty Images) (Tim Nwachukwu/Getty Images)

Houston Rockets v New York Knicks NEW YORK, NEW YORK - FEBRUARY 21: Jabari Smith Jr. #10 of the Houston Rockets shoots the ball against Mitchell Robinson #23 of the New York Knicks during the second quarter at Madison Square Garden on February 21, 2026 in New York City. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and or using this photograph, user is consenting to the terms and conditions of the Getty Images License Agreement. (Photo by Ishika Samant/Getty Images) (Ishika Samant/Getty Images)

New York Knicks v Philadelphia 76ers PHILADELPHIA, PENNSYLVANIA - FEBRUARY 11: Mitchell Robinson #23 of the New York Knicks gestures against the Philadelphia 76ers in the third quarter at Xfinity Mobile Arena on February 11, 2026 in Philadelphia, Pennsylvania. The Knicks defeated the 76ers 138-89. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and or using this photograph, User is consenting to the terms and conditions of the Getty Images License Agreement. (Photo by Mitchell Leff/Getty Images) (Mitchell Leff/Getty Images)

New York Knicks v Philadelphia 76ers PHILADELPHIA, PENNSYLVANIA - JANUARY 24: Mitchell Robinson #23 of the New York Knicks dunks the ball during the second half against the Philadelphia 76ers at Xfinity Mobile Arena on January 24, 2026 in Philadelphia, Pennsylvania. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and or using this photograph, User is consenting to the terms and conditions of the Getty Images License Agreement. (Photo by Emilee Chinn/Getty Images) (Emilee Chinn/Getty Images)

New York Knicks v Atlanta Hawks ATLANTA, GEORGIA - APRIL 06: Mitchell Robinson #23 of the New York Knicks reacts after a basket against the Atlanta Hawks during the fourth quarter at State Farm Arena on April 06, 2026 in Atlanta, Georgia. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and or using this photograph, User is consenting to the terms and conditions of the Getty Images License Agreement. (Photo by Kevin C. Cox/Getty Images) (Kevin C. Cox/Getty Images)

2026 NBA Finals - Game Two SAN ANTONIO, TEXAS - JUNE 05: Mitchell Robinson #23 of the New York Knicks attempts to block a shot during the first quarter against the San Antonio Spurs in Game Two of the 2026 NBA Finals at Frost Bank Center on June 05, 2026 in San Antonio, Texas. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and or using this photograph, User is consenting to the terms and conditions of the Getty Images License Agreement. (Photo by Gregory Shamus/Getty Images) (Gregory Shamus/Getty Images)

Cleveland Cavaliers v New York Knicks NEW YORK, NEW YORK - APRIL 11: Craig Porter Jr. #9 of the Cleveland Cavaliers attempts a layup while defended by Mitchell Robinson #23 of the New York Knicks during the first quarter of the game at Madison Square Garden on April 11, 2025 in New York City. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and or using this photograph, User is consenting to the terms and conditions of the Getty Images License Agreement. (Photo by Dustin Satloff/Getty Images) (Dustin Satloff/Getty Images)

By Frank O'Laughlin

BOSTON — The Boston Celtics have reportedly signed a free-agent center who brings elite defense, rebounding, and valuable playoff experience.

After signing Mike Conley, a 19-year veteran point guard, Boston added former New York Knicks role player Mitchell Robinson to a three-year, $47.4 million deal, according to Shams Charania.

Robinson, an eight-year veteran, averaged 5.7 points and 8.8 rebounds in 60 regular-season games for the NBA Champion Knicks last season.

Robinson has appeared in 53 postseason games for the Knicks over the last four years.

The seven-foot, 28-year-old also finished eighth in Defensive Player of the Year voting in 2025-26.

The NBA free agency negotiation period officially opened on Tuesday night. Official contracts can’t be signed until Sunday, July 6.

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