Inspirational sports dramas usually share key elements — struggle, setbacks, perseverance and hard-fought triumph. Even more effective if the movie centers on a disadvantaged protagonist, either economically or physically, to inject that underdog spirit. Debuting director William Goldenberg has all of that in Unstoppable, the incredible true story of wrestler Anthony Robles, who was born with only one leg but never let that stop him from going after his dream. The special sauce here, however, is the bond of love and support through tough times between Anthony and his mother Judy, stirringly portrayed by Jharrel Jerome and Jennifer Lopez. Goldenberg is an Oscar-winning editor whose collaborations with lead producer Ben Affleck stretch from Gone Baby Gone through last year’s Air. The latter is an entertaining account of a pivotal moment in the evolution of Nike and there’s a pleasing continuum in the fact that Robles was the first sportsperson signed as a Nike Athlete after he had retired from competitive participation in his field. This moving portrait of him will open in select U.S. and …