Datsyuk was entering the final year of a seven-year, $46.9 million contract and would become an unrestricted free agent next season. That means that the extension won't begin until the 2014-15 season and will carry through until the completion of 2016-17.
The financial terms of the agreement have yet to be released.
Datsyuk's agent, Gary Greenstein, previously told Ansar Khan of MLive.com that the two sides were close to an extension. Greenstein told Khan that he was flying into Detroit on Monday to speak with Red Wings manager Ken Holland. The agent stated that there was a good possibility that an agreement would be reached by week's end.
While Datsyuk tweeted that he has signed the deal, the agreement can't be officially submitted to the league prior to July 5.