Kasey Keller has warned Tottenham it is time for the club to decide whether it is serious about gatecrashing the top four.

The former Spurs goalkeeper has been watching on from afar as all the optimism generated by a superb run in last season's Champions League has threatened to evaporate.

Not only did Harry Redknapp's men fail to retain a place in Europe's elite club competition, now star man Luka Modric is demanding a move to Chelsea.

So far, Tottenham has resisted.

However, Keller expects Modric to get his way eventually, which would merely confirm his old club's status as sellers.

"Spurs have had this problem for years," Keller said.

"I don't see Manchester City selling their players to rivals. Manchester United don't do it.

"Maybe Arsenal are a little bit different but their fans are upset about that. If you want to be one of the big boys you have to act like it."

To Keller that means retaining your top players and adding to them.

During his three seasons at White Hart Lane in the early 1990s, the 41-year-old got used to star men being sold on.

It was still happening three years ago when Dimitar Berbatov went to Manchester United and if Modric does end up at Stamford Bridge, it would appear nothing much has changed.

"Your best players should want to stay," he said.

"They should not want to leave because they know they are going to be challenging for trophies.

"Tottenham have to reach that stage. At some point they must make a decision.

"Are they going to honestly and truly compete with these teams or are they just going to hope it all comes together at the right time and challenge for a year or two."

Keller is crossing his fingers Tottenham have the ambition.

Unfortunately, the veteran keeper, who is expected to feature for the Seattle Sounders in their friendly against Manchester United on Wednesday, believes history is against it.

"They have been in this position for the past 20 or 30 years," he argued.

"You can't cut corners and expect to compete at the highest level.

"You can't sell your top players if you want to compete with teams that don't.

"History says of course they will sell Modric. He will get mad enough and finally someone will give them a number that they can't turn down.

"Until that changes, everyone thinks that is what will happen."