Arozarena, a 24-year Cuban native, has batted .349 with 10 home runs and 16 stolen bases while playing both at Class AA Springfield and Class AAA Memphis this year.
At Memphis, Arozarena had reached base safely in 37 consecutive games, including hitting for the cycle. He has hit .368 with a .442 on-base percentage and .568 slugging percentage for the Redbirds.
Arozarena will wear uniform No. 66. He joins the club’s 40-man roster with his purchase from Memphis. That roster had been at 39.
Martinez was injured when he banged into the wall chasing a fly ball on Sunday.