The Mirror says Kagawa spent just 11 hours to undergo his medical at Manchester United.
He left Tokyo o begin his gruelling 13,700-mile round trip, took his medical and now has returned home.
The Japan midfielder didn't even have time to visit Old Trafford before he jumped on his plane back to Tokyo.
Kagawa said as he left Tokyo's Narita airport: "It's just a medical. I hope it will end with no problems."