The France international was thought to be a top target for Jose Mourinho, but a transfer failed to materialise due to Atletico's ban.
The Spanish club have been prohibited from registering new players until January 2018 after breaking rules relating to the signing of foreign players under the age of 18.
It is believed that out of respect for Atletico, Griezmann opted against pushing for a move away, but Balague has suggested that the forward could switch to Old Trafford next summer.
The Spaniard told Sky Sports News: "He is with a team which has played in Champions League finals and also won the league recently - more recently than Manchester United - so he is already at one of the top teams in Europe.
"He is playing with the fans and he will continue to do that with teasing messages but it is quite clear he will consider a move to Old Trafford next summer. This summer it's impossible but next summer, who knows?"
United ended up buying Romelu Lukaku from Everton for £75m in order to boost their attacking lineup.