The 23-year-old had 21 goals and 25 assists in 81 games last season with a plus-6 rating in a breakthrough campaign.
The deal, which begins during the 2027-28 season, carries an average annual value of $4.65 million.
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The league announced home openers for all 32 clubs Wednesday.
Mantha joins the Devils as new general manager Sunny Mehta’s latest addition to bolster the roster after missing the playoffs.
Krebs set career highs with 12 goals and 27 assists last season.
Hayley Wickenheiser and the Toronto Maple Leafs are parting ways after the hockey Hall of Famer spent eight seasons working in the NHL team’s front office.
The names of Carolina Hurricanes owner Tom Dundon’s wife and five children follow his before getting to members of the front office, coaches, and players.
Carlsson now is the NHL’s highest-paid player.
Connor Bedard is expected “to make a full recovery in an approximate timeline of four months.”
Utah would have received the Devils’ 2027 second-round pick as compensation if it did not match.
The Hearst, Ontario, native played the past four seasons with the Senators.
Daniel Alfredsson, once public enemy No. 1 in Toronto as captain of the Ottawa Senators, is leaving Canada’s capital to join the Maple Leafs as an associate coach.
