The 46-year old was discussing the Tottenham coach's career ahead of the Europa League clash between the Italian giants and the north London club and was scathing in his assessment of the Portuguese.
"Andre Villas-Boas is an average coach," he told Radio Mana Sport.
"He proved that with Chelsea and at the moment with Tottenham. He should be doing much better, you just have to look at their [eighth place] ranking in the Premier League table to see that.
"He is unable to give clear instructions to the team, and only with Porto has he done a good job, and even then he had the best players available to him."
Rambaudi did point out that Spurs will be a test for Lazio in the Europa League clash and singled out a number of key men who could cause the Biancocelesti problems.
"Despite all of that, Tottenham are one of the strongest teams in England," he added.
"Gareth Bale, Jermain Defoe and Aaron Lennon are three of the best attacking players in the world and I think Lazio will have to be careful not to leave too much space on the wings for those players to attack.
"I trust the coach, Vladimir Petkovic, to take the right measures and choose the right players to counter this problem."