Former Tottenham Hotspur owner Lord Alan Sugar has slammed Andre Villas-Boas, calling the ex-Spurs boss "unprofessional" and "immature".

Villas-Boas's 18-month tenure at the helm of the club came to an end earlier today when he was sacked having seen his side thrashed 5-0 by Liverpool at White Hart Lane on Sunday.

The former Chelsea boss spent heavily during the summer transfer window due to the world-record sale of Gareth Bale to Real Madrid, and Sugar believes that his transfer policy showed a lack of professionalism.

"The fact is he's gone. With the greatest respect to the chairman, I think it was the wrong move to appoint him. I think the guy showed he was unprofessional in spending that amount of money," Sugar told ITV Sport.

The 66-year-old later reiterated his views and claimed that the dealings in the transfer window also showed immaturity and could have been the beginning of the end of Villas-Boas.

"I can only imagine there must have been some words which were not acceptable by the manager spoken between him and the chairman and that is why it abruptly ended," Sugar told Sky Sports News.

"Young fellow AVB - he has his own ideas and I don't think he wants to listen to anyone else other than himself. He tried to implement those ideas and the thing is they didn't work. The writing was on the wall as far as I was concerned when he went out and spent like a a kid in a sweet shop, I mean you just can't do that.

"It doesn't stack up, you just can't go out and buy seven brand new players or whatever it was, stick them in and hope for them to play. It showed immaturity."

The likes of Fabio Capello and Glenn Hoddle are among the early frontrunners to replace Villas-Boas at White Hart Lane.