The signing reunited him with former Boston Red Sox teammate David Ross .
In December 2014 , Lester agreed to a six - year , $155 million deal with the Chicago Cubs with a vesting option for a seventh year at $15 million .
The signing reunited Lester with former Boston Red Sox teammate David Ross .
In December 2014 , Lester agreed to a six - year , $155 million deal with the Chicago Cubs with a vesting option for a seventh year at $15 million .