Joe Hart was among a handful of big names back at Manchester City for their first day of preseason training on Monday.
City boss Pep Guardiola returned to the Etihad Campus without the vast majority of his senior players due to their World Cup commitments.
Hart, who has spent the last two seasons on loan, firstly at Italian side Torino and last year with West Ham, was back at City after being left out of Gareth Southgate's England squad.
The 31-year-old has 12 months remaining on his contract and sources have told ESPN FC that he is seeking a permanent move away before the start of the season.
Several other loan players, including Brazilian midfielder Douglas Luiz and former New York City winger Jack Harrison, are also at the Etihad Campus.
Some young and fringe players will have the chance to stake their claim for first-team opportunities as part of the preseason International Champions Cup in the United States this month.
However, defender Eliaquim Mangala, who spent the first half of last season with the first team before going out on loan to Everton, is in Spain for rehabilitation on a knee injury.
City still have seven players competing at the World Cup this week, and a further nine players will return later after being given extra time off because of their involvement in Russia.
PFA Young Player of the Year Leroy Sane will join up with the first team on their preseason tour to the United Sates after being a part of Germany's pre-tournament training squad.
Young midfielder Phil Foden was at the Etihad Campus although a decision has not yet been named on whether he will be part of the England squad for the under-19 European Championships, which starts on July 16.
Clubs are not obliged to allow players to join up with England for the tournament in Finland and with Foden seen as a first team, Guardiola could decide to take him to the U.S.
City are still to make any new signings in the transfer window with Leicester City's Riyad Mahrez and Napoli's Jorginho remaining the club's top two targets.
Young midfielder Manu Garcia, who impressed on loan at Dutch side NAC Breda last season, has joined Ligue 1 club Toulouse on loan while fellow midfielder Aleix Garcia is set to return to Spanish side Girona on loan.