Shattenkirk, 30, played 119 games with the Rangers over the past two seasons, scoring 51 points (7 goals, 44 assists) with a minus-29. But his game never recovered after an injury-filled first season with the team, and his 1.4 shooting percentage last season was the worst of his career.
His contract carried an average annual value against the salary cap of $6.65 million through 2021. According to Cap Friendly, the Rangers will save $5,166,667 million against the cap this season, as Shattenkirk's cap hit would be reduced to $1,483,333 in 2019-20.
The buyout will be spread out over the next four seasons, with the Rangers also paying him $6,083,333 in 2020-21, and $1,433,333 in 2021-22 and 2022-23.
"Today's decision was a very difficult one," Rangers president John Davidson said. "Kevin is a great person and teammate and he was extremely proud to be a New York Ranger. We wish him and his family all the best going forward."
After handing out big contracts to new acquisitions in winger Artemi Panarin ($11,642,857) and defenseman Jacob Trouba ($8 million), the capped-out Rangers needed room to sign restricted free agents Brendan Lemieux and Anthony Deangelo.
The cap hit for Shattenkirk next summer still leaves New York with more than $16 million in projected room under the ceiling.
His tenure with the Rangers will be filed under "be careful what you wish for." After a year splitting time with the St. Louis Blues and Washington Capitals, Shattenkirk became a coveted unrestricted free agent in the summer of 2017 as one of the NHL's better puck-moving defensemen. Spurning longer-term deals, he signed a four-year, $26 million contract with the Rangers on July 1, his favorite team as a child while growing up in New Rochelle, where his parents still live.
"It's an opportunity that may only come once in my career, and I felt like this was my chance," Shattenkirk said at the time. "It's a team I'm extremely excited about. A lot of the factors outside of money and term came into play, and that's ultimately what won the decision for me."
But in his first season with the Rangers, the team's objectives changed. Veterans Ryan McDonagh and J.T. Miller were traded, and the team announced to its fans that it was entering a rebuild. Now, with a slew of young players that includes No. 2 overall pick Kaapo Kakko and big-name additions like Panarin and Trouba, the Rangers' timeline and economics no longer sync up with their need for Shattenkirk.