The 28-year-old Blues midfielder will now be desperate to impress Fabio Capello on Sunday and his namesake, Ashley, is urging the England coach to take his team-mate to the World Cup.
He said: "To be around Joe, he is a great guy, he is funny and always making jokes. But he is one of the hardest trainers I have ever seen.
"He seems to think if he doesn't play he has to train harder which is brilliant from him and all the [Chelsea] players are pleased he is in the provisional 30.
"I think he has started to find his feet again now. Of course he came back from a major injury and was out for a long time but he is very fit and is looking very sharp. Hopefully all the Chelsea players will be on the plane to South Africa together."