The 33-year-old defenseman played this season for the Philadelphia Flyers after they acquired him in a trade from the Washington Capitals for defenseman Radko Gudas on June 14, 2019. He had one season remaining on a seven-year, $40.25 million contract ($5.75 million average annual value) he signed with Washington on July 1, 2014.
"Thank you to the Flyers organization for the opportunity to play in [Philadelphia] last season," Niskanen said. "I'd also like to thank the fans for their support and lastly, I wish my teammates the best of luck."
Niskanen was second among Flyers defensemen with 33 points (eight goals, 25 assists) in 68 games, playing most of the season on the top defense pair with Ivan Provorov. Niskanen averaged 23:04 of ice time and had one goal and one assist in 15 postseason games for Philadelphia, which lost in six games to the New York Islanders in the Eastern Conference Second Round.
"I want to thank Matt Niskanen for his contributions to the team this season," Flyers general manager Chuck Fletcher said. "He's the consummate professional and teammate. Besides his on-ice contribution, he contributed so much to our group from the way he prepared, from the way he practiced, he did everything the right way in drills, which was a great lesson for a young defenseman to watch day in and day out.
"For us, he was a top-pairing defenseman, played on the second power play, the first PK, was used in every situation. If we were up a goal in a game, he was on the ice, [and] he was often on the ice when we were down a goal trying to tie it up. He certainly won't be an easy player to replace. Today should be about thanking Matt for what he did, for what he contributed to our group. I think we're very grateful for the time we had with him."
Selected by the Dallas Stars in the first round (No. 28) of the 2005 NHL Draft, Niskanen scored 356 points (72 goals, 284 assists) in 949 regular-season games with the Flyers, Capitals, Pittsburgh Penguins and Stars, and 42 points (six goals, 36 assists) in 140 playoff games. He won the Stanley Cup with Washington in 2018.
