Lionel Messi surprised fans by appearing in the latest Spider-Man: Brand New Day teaser alongside Tom Holland. The playful cameo shows Messi searching for Spider-Man before joining the superhero on an action-packed adventure. Fans flooded social media with jokes, calling the football icon's Marvel appearance unexpected. The crossover also revived memories of Messi's Marvel-inspired goal celebrations, which he previously revealed were inspired by watching superhero movies with his children.Lionel Messi has added another memorable moment to a memorable year – but this time it had nothing to do with football. The Argentine icon popped up in the latest teaser for Spider-Man: Brand New Day, sending social media into overdrive. Fans waited for news of the next Marvel movie. Instead they were watching one of football’s greatest players share the screen with Tom Holland’s Spider-Man, in a crossover few could have imagined happening.Lionel Messi's Spider-Man: Brand New Day cameo sends social media into overdriveThe newly released teaser opens inside a small New York café, where Tom Holland's Peter Parker is relaxing before an unexpected visitor walks through the door. That visitor is none other than Lionel Messi.The playful clip leans into one of the biggest secrets in the Marvel Cinematic Universe. Peter Parker is secretly Spider-Man, yet Messi arrives holding a phone and tells Parker that he is using a "Spidey-tracker" because he is looking for the famous superhero. Parker tries to stay calm before quickly leaving the café.A few moments later, spider man returns in full costume and surprises the football legend. The teaser then goes full superhero as the pair jump off a building together, with Spider-Man using his web-slinging skills to keep Messi safe during the adventure.The surprise crossover instantly became a talking point on the internet. There were many fans who joked that Messi keeps finding new ways to surprise the world off the pitch.One fan wrote:"Messi is just doing side quests at this point😭"Another joked:"Messi doing anything but speak english 💀"Others embraced the crossover with humorous reactions, including:"Bro thought he was signing for Inter Miami but ended up in the MCU. 😭🐐""Type of shit I would type on Google when I was 8yo. Messi meeting Spider-Man."Some supporters even imagined a bigger Marvel future for the World Cup winner, posting comments such as "Messi will return in Avengers Doomsday," while another joked that "messi is the future spiderman lol." Others simply admitted that seeing Messi inside the MCU was something they never expected.The teaser arrives just weeks before Spider-Man: Brand New Day is scheduled to reach theaters on July 30, 2026.Meanwhile, Messi remains focused on football as he continues representing Argentina at the 2026 FIFA World Cup, where the defending champions have already reached the Round of 32.Lionel Messi's Marvel celebrations have a special family storyAlthough the new Marvel appearance surprised many viewers, Messi's connection with superheroes is nothing new.Soon after joining Inter Miami in 2023, he celebrated several goals by recreating famous poses from Marvel heroes, including Spider-Man, Thor, and Black Panther.Those celebrations quickly became fan favorites, but the inspiration came from a much more personal place.Speaking to the Miami Herald (h/t Diario AS), Messi explained that the tradition began because of evenings spent watching Marvel films with his children."With my three kids still on vacation and not yet back to school, we’ve been watching Marvel superhero movies every night. The idea came from them, and they asked me that every time I play a match and score a goal, I should do a Marvel superhero celebration."He added:"That’s how it all started, and we’ve kept up with that tradition.Every time we’d watch a new movie, we’d practice a goal celebration. But I only do them for home games, when the kids are here, close to me, so we can share those moments. When I see them in the stands, that’s when I perform them."That family tradition has now come full circle. What started as goal celebrations inspired by his children has evolved into an official Marvel collaboration, giving fans another memorable chapter in Messi's extraordinary career beyond the football pitch.