The duo are teammates since Pulisic arrived last summer, but they seem to have known each other as kids as well.
The Blues put up the photograph of the two and another youngster on social media, with the caption: “Look what @cmpulisic found in the archives! @masonmount10."
According to The Sun, the photo was taken at Cobham training ground in 2010, when the pair were both 11.
Christian Pulisic and Mason Mount go way back!
: @cpulisic_10 (June 2010) pic.twitter.com/tLMk3kzOuU
— Chelsea FC (@ChelseaFC) August 9, 2020