This is what the world’s best tennis players do when there’s a grassy patch near the tennis complex and they’re not involved in matches. Rafa Nadal, Novak Djokovic, et al., play a small-sided game at the BNP Paribas Open in Indian Wells, California.
By the way, is there a pickup game anywhere in the developed world that doesn’t include at least one Barcelona shirt? I’m going to guess “no”.