Nigeria have included four Premier League players in their provisional squad for the Rio Olympics.
Arsenal starlet Alex Iwobi has been named in the 35-man contingent, along with Man City's Kelechi Iheanacho, Chelsea midfielder John Obi Mikel and Watford striker Odion Ighalo.
However, they face a battle with the clubs to release the players as City are adamant Iheanacho will not travel to Brazil.
Boss Samson Siasa has also indicated Watford will not release Ighalo while there are doubts over Mikel's ability.
The competition runs into August with players set to miss the first month of the Premier League season.
City have already informed the Nigerian Football Federation that Iheanacho will not be allowed to compete, reports the Manchester Evening News.
The club want the teenager to be available for Pep Guardiola's first pre-season after an impressive breakthrough campaign last term.
City are under no obligation to make Iheanacho available and have already spoken to him about the issue.
Arsenal meanwhile have no plans to block Iwobi's call-up with Arsene Wenger previously backing his player to impress in Rio.
“He had the choice between England and Nigeria and in the end he chose Nigeria,” Wenger said.
“We respect that, and also the possibility that he will go to the Olympic Games, that he will also go to the Africa Cup of Nations and travel a bit more than he would have done here.”