Tom Hiddleston joined Instagram yesterday, marking his Insta-debut with a snap of himself in costume as his Marvel alter-ago Loki. 

But he had only been a member of the social media platform for mere minutes when he was subjected to his first Taylor Swift joke...

His Marvel co-star Robert Downey Jr was the culprit. He couldn't resist poking fun at the actor for the time he wore that 'I heart T.S.' vest. (And we can't really blame him.)

"Join me in welcoming the biggest T. Stark fan of them all to Instagram! @twhiddleston," Downey Jr wrote, alongside a snap of Hiddleston in his Swift shirt. 

 

Join me in welcoming the biggest T. Stark fan of them all to Instagram! @twhiddleston

A photo posted by Robert Downey Jr. (@robertdowneyjr) on Aug 9, 2016 at 3:09pm PDT

See what he did there? Ignoring Hiddleston's very public love affair with mega popstar Swifty, Downey Jr instead opted to interpret the top as a declaration of love for his character Tony Stark.

Nicely done, Iron Man.