Complex sentence: Nix did not consent to being reselected by the Astros in the 2015 Draft and was selected by the San Diego Padres in the third round, with the 86th overall selection, of the Draft.
Split into simpler sentences: Nix did not consent to being reselected by the Astros in the 2015 Draft. The San Diego Padres selected Nix in the third round, with the 86th overall selection, of the Draft.