That commitment, of course, would ultimately lead Jennifer Lopez to become “Jenny from the Block,” apparently receiving much inspiration to do so while shooting the opening scene of Selena, depicting one of the singer’s final performances at the Houston Astrodome. The sequence was actually filmed at the San Antonio Alamodome, as reported by the Chicago Tribune, for which approximately 34,000 fans of Selena showed up to fill the venue as extras for no pay. Lopez recalled the experience as initially overwhelming, but soon found it to be “amazing,” adding, “There was a lot of love. I felt it channeled to me. It made me feel more confident. After I saw how I was received that day, it made it a lot better.”
Article source: https://www.cinemablend.com/news/2549803/selena-behind-the-scenes-facts-about-the-jennifer-lopez-movie