The pair share a strong bond at San Siro, often watching NFL games together, but the Mexican joked that friendship ends on the international stage.
Gimenez currently sidelined with an ankle injury, joined Milan in February 2025 from Feyenoord, while Pulisic, at the club since 2023, has been posting career-best numbers.
“If we play a game (for our countries), we are enemies, we are rivals. But in the dressing room, he's one of my best friends,” the Mexican told ESPN.
“We are always together, and I hope, if he's not playing against Mexico, that he does well. But if he's playing against Mexico, of course if I need to kill him, I kill him!
“But he was a really good friend in this difficult moment (of injury rehab). We have a lot of things in common.
“We like NFL - he supports the Jets, I like the Dolphins. Sometimes, I go to his house and do a barbecue and watch the NFL. So, he's a nice team-mate, a nice friend, but in the end, if he puts on the shirt of the USA, he's a rival.”