Dec 29, 2009 4:13 PM EST

Free-agent outfielder Jason Bay has agreed to a four-year, $66 million contract with the Mets.

A source confirmed the agreement to ESPN.com on Tuesday.

The agreement will become official when Bay takes a physical at some point next week.

The deal reportedly includes a vesting option year that could increase Bay's overall payout to slightly more than $80 million over five years.

Via ESPN