The Brazilian has returned to Manchester from his post-World Cup holiday and is still recovering from damaged ligaments in his left ankle.
Having touched down at Manchester Airport, the City full-back took to Instagram to share the worrying image and can be seen sitting down while waving crutches.
He sustained the injury in a training session during Brazil’s World Cup campaign and was forced to miss their quarter-final defeat by Belgium.
Manager Pep Guardiola had hoped to see Danilo return in time for City’s Premier League opener at Arsenal in under two weeks as scans revealed he did not require keyhole surgery.
The former Real Madrid man started Brazil’s opening group game against Switzerland but then picked up a hip injury, which kept him out until the last 16, when he was back on the bench as they beat Mexico.
Danilo had to wear his protective boot while on holiday, but his latest post clearly shows the boot still remains as he is due to return to pre-season training.
If the injury is worse than first thought, Guardiola may be short of right-back options for the start of the season with Kyle Walker not due back in training until next week following his involvement with England in the World Cup third-place play-off.