This World Cup tournament includes three separate opening-ceremony performances highlighted by major pop artists. Coverage centers on a comparison of the star power of three acts: Shakira, Michael Bublé, and Katy Perry. The discussion frames the ceremonies as distinct events within the same tournament, each showcasing a different headline performer. However, the provided excerpts do not include details such as the specific host countries for each artist, the dates of the ceremonies, what songs or segments were performed, or any audience and viewership metrics. They also do not provide a definitive result to the implied “battle” question about which opening ceremony commanded the most attention. Instead, the articles primarily set up the topic for readers by naming the three featured artists and noting that there are three opening ceremonies rather than one. Based on the available information, the consistent point across sources is that Shakira, Michael Bublé, and Katy Perry are each associated with one of the tournament’s opening ceremonies.