The Argentine full-back made the move from Manchester City to the Hammers earlier this summer and was followed by Hart earlier this week.
The English international goalkeeper has signed a season-long loan deal at the London Stadium side and is expected to be the Hammers number one for the new campaign.
He’s got a lot of experience from his time at Manchester City and Torino, as well as his 71 caps for England.
But that doesn’t get Hart an easy time of it in West Ham training after arriving at the club.
Teammate Zabaleta belted a volley beyond him in training yesterday and followed it up by saying: “Welcome to West Ham, my friend.”:
"Welcome to West Ham, my friend." ? pic.twitter.com/M1r94rcQq9
— West Ham United (@WestHamUtd) July 20, 2017
If anyone else had said that, you’d think it was a little mean, but Zabaleta and Hart know each other well so it’s all in good fun.
Hammers fans could see Hart in action for the first time when their side take on Fulham in a friendly later tonight.
But if he doesn’t get a run-out then it’s almost certain he’ll get some game time against Werder Bremen a week tomorrow.