Griezmann was United’s top transfer target but despite admitting a move to Old Trafford was a possibility, he instead decided to sign a new contract at Atletico after the club were handed a transfer ban.
And the contract wasn’t the only thing new about Griezmann upon his return to training, as the striker surprised his team-mates by sporting a shock of bleached blonde hair.
The France international was pictured linking up with the squad at their training base in Los Angeles de San Rafael, Spain, in photos posted to Atletico’s Twitter account.
Griezmann was shown embracing midfielders Gabi and Nicolas Gaitan as he met up with the team for the first time since signing a five-year contract with the club.
Atletico’s players were later put through their paces in the Spanish sunshine as they prepare for their first season at the Wanda Metropolitano Stadium.
Griezmann and Koke were the last remaining first team players to join up with Atletico’s squad after they were given extra time to recover after a gruelling season.
Diego Simeone’s side have been at the base since July 6, though Jan Oblak, Diego Godín, Jose Gimemez, Stefan Savic, Filipe Luis and Yannick Ferreira Carrasco didn’t report to training camp until Saturday.
Atletico finished the campaign in third place in La Liga and advanced to the Champions League semi-finals before being knocked out by city rivals Real.
They open their pre-season fixtures with a trip to face Mexican side Deportivo Toluca on July 26 before ties with Napoli and Premier League new boys Brighton.