Edwin van der Sar does not think Ajax coach and close friend Frank de Boer is ready for the national team job.The Netherlands were dumped out of this summer's European Championship without taking a single point from their three group matches, leading to calls for coach Bert Van Marwijk's head.

Van der Sar advised De Boer to gain more experience and consider a move to another top European club before he thought about leading his country.

"Not right away but I think 6-7 years from now is a good time (for De Boer to coach the Netherlands)," Van der Sar told Goal.com.

"I think he could coach another big club from abroad, then maybe go for the national team."

Ajax have won two consecutive Eredivisie championships under de Boer and Van der Sar hoped they could carry their domestic form into the Champions League during the 2012-13 season.

"Frank de Boer is a very good friend of mine, so he's doing really well and after winning two league titles in a row I think the team's doing extremely well," Van der Sar said.

"Hopefully this year they can do well in the Champions League. That's the main thing so I hope they can be ready for that also."

As for his own future in management, Van der Sar was unsure as to what could lie ahead but hinted that the Ajax job would be difficult to turn down.

"I don't know," Van der Sar added. "I think it depends on the offer.

"I think I had a good time with all of them (the clubs he played for). I moved back to Holland. Ajax could be a good one, but I'm not looking at the moment."