Rivas went 2-for-4 with a home run, two runs scored and five RBI in Wednesday's win over the Pirates.
The home run was a memorable one, as Rivas went deep in the ninth inning with the bases loaded. It was the third home run of the season for the 25-year-old and the first grand slam of his career. Rivas spent some time at Triple-A Iowa recently, but with Frank Schwindel (back) landing on the injured list, the former may see more playing time in the short term.