The Cubs finalized a deal with Japanese lefty Shota Imanaga on Wednesday, agreeing to a four-year, $53 million contract, sources familiar with the situation told ESPN.

The deal has several provisions, including the team's option to extend the contract -- after both Years 2 and 3 -- to $80 million over five years. But if the Cubs decline in either year, Imanaga can choose to become a free agent or remain in the original contract.