The deal is for $8.25 million, a source told ESPN's Buster Olney.
The Red Sox never went beyond two years in their offer to Jarrod Saltalamacchia, according to a source. The 28-year-old catcher agreed to a three-year, $21 million contract with the Miami Marlins pending a physical exam, a baseball source told ESPN.com's Jerry Crasnick.
The well-traveled Pierzynski turns 37 on Dec. 30, but he has played in at least 125 games in each season since 2002, has hit a total of 44 home runs in the past two seasons (27 with the Chicago White Sox in 2012, 17 with the Texas Rangers this past season), and he threw out 33 percent of the runners who attempted to steal on him in 2013, his best rate in more than a decade.
Saltalamacchia was the better offensive player in 2013, with his .804 OPS more than 80 points higher than Pierzynski's .722.
The left-handed-hitting Pierzynski will complement right-handed-hitting David Ross behind the plate for the Red Sox. The short-term deal would seem to be an indication that the team believes catching prospects Christian Vazquez and Blake Swihart might be ready for the majors sooner than later.