Designated hitter J.D. Martinez, who missed the New York Mets’ three-game sweep of the Boston Red Sox this week, was activated from the paternity list on Thursday.In a corresponding move, the Mets optioned outfielder DJ Stewart to Triple-A Syracuse.The Mets also claimed outfielder Jose Azocar off waivers from the San Diego Padres and assigned him to Syracuse. Right-hander Sean Reid-Foley (right shoulder impingement) was moved to the 60-day injured list.In his first season with the Mets, the 37-year-old Martinez is hitting .252 with 16 homers and 65 RBIs in 105 games.Stewart, 30, is hitting .175 with five homers and 19 RBIs in 72 games this season.