The Premier League rivals played to a goalless draw in a pre-season friendly at the M&T Bank Stadium in Baltimore on Saturday night in a match which saw striker Fabio Borini debut for the Reds.

Villas-Boas heavily criticised midfielder Adam, who has had altercations with Bale in the past, with the Spurs boss saying the knock could cost his team as the start of the new season draws near.

The Scotland international came under fire for injuring the Welshman in a tackle in May 2011 - an incident which Villas-Boas only came to hear of after Saturday's encounter.

Bale suffered ankle ligament damage and was out for three months after that clash, and Villas-Boas has now expressed his dismay at the second incident of a similar nature.

He told PA Sport: "I think it was a very nasty challenge from Charlie. The player had gone and he came in from behind on Gareth's ankle. I did not know the previous history between the two. I do now.

"It is a difficult one to be fair. You do not want to end up in a game with Liverpool with 10 men.

"At half-time Charlie came to me and said something about the challenge. I can accept that but I think he should go to the player to say sorry."

He added: "If the player escapes hospital it is because he is very lucky. The last time he was out for three months and in the end it is the Premier League that suffers without a player of Bale's talent."