Kovy is NHL's costliest acquisition

Ilya Kovalchuk's retirement ended his time with the Devils after 222 games. Andy Marlin/Getty Images

New Jersey Devils forward Ilya Kovalchuk, one of the game's top scoring threats, stunned the hockey world Thursday when he announced he was retiring from the National Hockey League.

"This decision was something I have thought about for a long time, going back to the lockout and spending the year in Russia," Kovalchuk said in a statement released by the team.

The 30-year-old winger had 12 years and $77 million remaining on the 15-year, $100 million contract he signed with New Jersey in September 2010, inking that deal after establishing himself as one of the league's top snipers. Kovalchuk twice scored 50 goals in a season and topped 40 in four others.

There have been other marquee players who have moved on, most notably when the Edmonton Oilers Oilers traded Wayne Gretzky to the Los Angeles Kings for Jimmy Carson, Martin Gelinas, $15 million in cash and the Kings' first-round draft picks in 1989, 1991 and 1993. But even that trade wasn't nearly as costly as what New Jersey has paid, and will continue to pay, for Kovalchuk.