LOS ANGELES—J.D. Martinez and David Peralta homered back-to-back in the fifth inning, helping the Los Angeles Dodgers rally from a four-run deficit to beat the Pittsburgh Pirates 6–4 on Wednesday night, July 5. Martinez connected on an 0-2 pitch from reliever Roansy Contreras (3–7) for his 20th homer, a go-ahead, three-run shot to left-center that…