Permian endorsed form out of The Derby with a determined victory in Friday's Group II King Edward VII Stakes (1m3f211yds) at Royal Ascot.
Permian (6/1) finished 10th at Epsom and after striking the front around the home turn stayed on strongly to hold the late rally from Khalidi (10/1), 14th at Epsom, by half a length.
The 9/4 fav Crystal Ocean, third to Permian in the Group II Dante Stakes at York, made a forward move from midfield around the home turn before staying on one pace to be beaten 1 3/4-lengths into third.
Trainer Mark Johnston has never been one to shy away from a fight and he told Racing UK he was happy to run despite the Derby failure.
"We were always thinking he had improved but he didn't run to his Dante form at Epsom," Johnston said.
"The horse came back so well from there that we felt we had to run. He lost more weight in the Derby than he has in any other race but he put it all back on.
"I spoke to Sheikh Hamdan and he said if the horse is well then to go ahead and run.
"I'm a great believer in running them and galloping them at the races and not at home. I think we've got a problem here in Britain that we tend to judge horses more on defeats than their wins."
Permian defeated Thursday's Group III Hampton Court Stakes winner Benbatl when winning the Group II Dante Stakes in May and jockey William Buick said the son of Teofilo failed to handle the day at Epsom.
"We were surprised after the Derby, he didn't feel at ease at Epsom. Today he's won it really well, he stayed well," Buick said.
"I think he's still improving - you take the Derby away and he's a very exciting colt."