The deal is pending a physical, a baseball official with knowledge of the agreement said Friday. The official spoke on the condition of anonymity because the contract had not been finalized.
Mirabelli will get a $550,000 base salary. He can make $275,000 more in roster bonuses, $150,000 in conditioning bonuses and $1.25 million in performance bonuses based on games and games started.
Since batting a career-high .281 and playing a key role in Boston's 2004 World Series title, Mirabelli has averaged just six homers and 20 RBIs with a .206 batting average while playing in just 30 games a season.
But the Red Sox have seen what life was like without Mirabelli catching for Wakefield -- and it wasn't good.
Mirabelli spent four years in Boston before he was traded to San Diego after the 2005 season, and Josh Bard was given the responsibility for catching Wakefield. But Bard struggled in the role, allowing 10 passed balls in the knuckleballer's first four starts before the team made another deal with the Padres to get Mirabelli back.
When he returned on May 1, 2006, Mirabelli got a police escort from the airport and changed into his uniform in the back seat of a car in order to be ready to catch Wakefield's start against the Yankees. He got a standing ovation when he took the field.
But Mirabelli hasn't been as successful on offense.
He batted .191 in 2006 and .202 last season, when he earned a base salary of $750,000.