Kovalchuk's agent and the team announced Monday the biggest prize of the NHL free-agent market agreed to a new contract. It ends weeks of speculation where the high-scoring left-winger would play next season.
Details were not immediately available, but ESPN is reporting that the deal is for 17-years, and could top $150 million.
"This was a long arduous process that has taken frankly a little longer than I thought," agent Jay Grossman said in a telephone interview with The Associated Press. "But you know what, nothing is worth anything unless you work for it.
"I can tell you he is very happy to be with the New Jersey Devils."
The Los Angeles Kings, New York Islanders, Devils and SKA St. Petersburg of Russia's Kontinental Hockey League talked with Kovalchuk since free agency started July 1.
The final decision came down to the Kings and Devils. New Jersey will officially reintroduce Kovalchuk to New Jersey at a news conference Tuesday.
Grossman refused to say Kovalchuk decided to stay because he felt the Devils had a better chance to win the Stanley Cup.
"This was so far complex that I don't want to get into those questions," Grossman said. "Obviously his goal is to win the Stanley Cup.
"If he didn't think there was an opportunity to do that, then he would not have gone there."
Neither Devils president and general manager Lou Lamoriello nor star forward Zach Parise immediately returned telephone messages seeking comment.
The team's only major loss during the off-season was defencemanPaul Martin, who signed with the Atlantic Division-rival Pittsburgh Penguins.
Kovalchuk, 27, was traded to the Devils by Atlanta in February after rejecting a 12-year, US$101-million extension offered by the Thrashers.
Kovalchuk had 41 goals and 44 assists last season while earning $7.5 million. But he posted only 10 goals and 17 assists with the Devils.
When the trade with the Thrashers was completed, Lamoriello felt his team finally had the goal scorer it needed to make a run at a fourth Stanley Cup title since 1995.
It didn't work out that way. Kovalchuk had two goals in the post-season, but the Devils were eliminated by the Philadelphia Flyers in five games in the opening round. It was New Jersey's third straight exit in the first round.
Kovalchuk has won only one playoff game in his NHL career.
The Devils have been very active since the playoffs ended. John MacLeanwas named the new coach, replacing the retired Jacques Lemaire. The team reacquired veteran centre Jason Arnott in a trade and signed defencemen Henrik Tallinder and Anton Volchenkov and goalieJohan Hedberg in free agency.
The first pick overall in the 2001 NHL draft, Kovalchuk has scored 338 career goals, the most by any player in the league in that period. He has only been to the playoffs only twice in eight NHL seasons.
Kovalchuk was acquired from the Thrashers along with defencemanAnssi Salmela for forward Niclas Bergfors, defenceman Johnny Oduya, prospect Patrice Cormier, a first-rounder and a swap of second-round picks.