Tottenham Hotspur goalkeeper Paul Robinson believes the club were wrong to sell Michael Carrick to one of their rivals.
The England midfielder joined Manchester United earlier this summer for £18.6 million but his former team-mate is not sure his club have made the right decision.
Robinson cites the other top clubs' refusal to sell their best players to Premiership rivals and feels if Spurs are to make the step-up, they need to be keeping their stars at White Hart Lane.
However, the former Leeds goalkeeper admits the money will be very useful in helping Martin Jol strengthen in weak areas.
"I thought it was a backward step, Manchester United are Tottenham's rivals and if we want to break into that top-four group, we shouldn't be selling to that top-four group," Robinson told the News of the World.
"Maybe Chelsea can afford to do it, but you don't see United and Arsenal selling to each other.
"What I would say, though, is that financially it was good business for the club - providing the money goes back into the team.
"If we lose a player of Michael's calibre and importance, it must benefit the areas that need strengthening."
Meanwhile, Robinson believes he can play at the very top level for the next 15 years.
The 26-year-old has already secured himself as England's number one and is aiming to continue to play for his country for many years to come.
He added: "I'm at a peak now. I'm the best in the country and my aim is to stay there for the next 15 years.
"I'm 26. I want to play at the top level until I am at least 40 and go another 12 years with England.
"David Seaman played to nearly that age and he was the first name on the team sheet for most of it. That is where I want to be.
"It gives me such a buzz when I hear the fans chanting 'England's number one'. That's my job now and as long as I keep doing it properly nobody can take it off me."