Michael Ballack has questioned Robinho's decision to snub Chelsea in favour of a higher wage at Manchester City.
City smashed the British transfer record with their £32.5million move for the former Real Madrid player on deadline day, amid their takeover by the Abu Dhabi United Group.
Chelsea had started the day as firm favourites to sign Robinho, but City's wealthy new owners beat them to the deal as Real became angered by the haggling over the Brazilian's price.
Ballack has queried the Brazilian's motives in heading to City when he could have stayed at Real or waited for the Chelsea deal to be completed.
"It is up to each player what they do, but if I were him, I would not have gone to Manchester City," Chelsea's German midfielder told newspaper Tagesspiegel am Sonntag.
"A transfer from Real Madrid to Manchester City is hard to justify with sporting reasons."
Reflecting on his own career trajectory, Ballack added: "I certainly do have a good contract here, but my career progressed.
"I did not go from Chemnitz to Bremen, although I had an offer from them, but I went to Kaiserslautern, who had just been promoted because I saw more chances for me to play there.
"Then I went to Leverkusen and not to Bayern, where I also had a contract awaiting my signature.
"Then in 2002, I went to Bayern and not Real Madrid, although I had a lucrative offer from them. And now I am at Chelsea, an absolutely huge club in the best league in the world at the moment.
"I feel very happy with Chelsea and in the city of London and I would happily end my career here." ended my career."