BOSTON – Former Boston manager Terry Francona gave Pedro Martinez a big hug along with some advice to help him in his new job as a special assistant to the Red Sox general manager.

“Now he’s going to have to be on time,” Francona needled his former pitcher Thursday when the two were reunited at the annual dinner of the Boston chapter of the Baseball Writers Association of America.

A three-time Cy Young Award winner and eight-time All-Star who spent seven seasons in Boston, Martinez returned to the city where he had his best years. His role is still undefined — he has the same title as former Red Sox catcher Jason Varitek — but Martinez said he would be willing to help with the pitchers, work in the minor leagues and generally be a friend to GM Ben Cherington.

“Varitek, Pedro, they are the Red Sox,” Francona said.

Martinez spent his first day back on the Boston masthead at a lunch with Cherington, new Red Sox manager John Farrell, CEO Larry Lucchino and Boston Mayor Tom Menino, and some civic leaders. Martinez said Menino had been welcoming to him when he first arrived in Boston in 1998 and again was forthcoming with advice about where to live and what to do in the city.

“Menino was a friend to me,” Martinez said.

Martinez was acquired from the salary-dumping Montreal Expos after the 1997 season, a few months before he would be awarded his first Cy Young. He instantly became the ace of the Red Sox staff, the biggest character in a colorful clubhouse and a key part of the team that won the 2004 World Series to end the franchise’s 86-year title drought.

Martinez said his experience with the team during that era can help players who are trying to recover from last season’s last-place finish.

“There was something missing, in the clubhouse, the players, around Fenway. This offseason they realized that they lost something,” Martinez said, noting that the addition of Farrell as manager, and players such as Shane Victorino and Mike Napoli.

“We have the right group of people. These guys coming in have great, great character.”

Martinez, 41, went 117-37 with a 2.52 ERA in Boston. His .760 winning percentage is the best in franchise history, and he ranks third with 1,683 strikeouts and sixth with 117 wins in a Red Sox uniform. He is also the franchise’s all-time leader with 80 postseason strikeouts; in the 1999 All-Star game at Fenway Park, he struck out the first four batters he faced.

“I am thrilled to be returning to this organization and to the city I love,” Martinez said. “It is an honor to be back with the Red Sox and help in any way I can. I am grateful to our leaders; I believe in them, and I thank them for allowing me to return to the field and help us win again.

“My heart will always live in Boston.”

Boston signed left-hander Craig Breslow, who had been eligible for salary arbitration, to a two-year contract with a club option for 2015.

DIAMONDBACKS-BRAVES: Arizona traded outfielder Justin Upton to Atlanta in a seven-player deal that sent infielder Martin Prado to the Diamondbacks.

The Braves also got third baseman Chris Johnson. Atlanta gave up four minor leaguers in the deal, including top pitching prospect Randall Delgado. The other minor leaguers headed to Arizona are right-hander Zeke Spruill, shortstop Nick Ahmed and first baseman Brandon Drury. Prado, projected to play third base for the Diamondbacks, can become a free agent after this season.

Upton, who has five-plus major league seasons but still is just 25, will join his older brother, B.J. Upton, who recently signed a free-agent contract with Atlanta.

METS: A person familiar with the deal said New York and free-agent right-hander Shaun Marcum agreed on a one-year contract.

WHITE SOX: Chicago acquired right-handed pitcher Zach Stewart off waivers from Pittsburgh.

NYJER MORGAN, a free-agent outfielder, signed with the Yokohama DeNA BayStars of Japan’s Central League.