Tottenham manager Andre Villas-Boas has criticised Liverpool midfielder Charlie Adam for a heavy challenge on Gareth Bale in their goalless pre-season friendly in the United States.

Spurs and Liverpool played out a 0-0 draw at the M&T Bank Stadium, home of NFL franchise the Baltimore Ravens.

In a game which marked the Liverpool debut of summer signing Fabio Borini, Villas-Boas was critical of Adam who has previous history with Bale.

In May 2011 the Scotland international injured Bale in a tackle, an incident Villas-Boas was only made aware of following game in Baltimore.

Bale was out for three months with ankle ligament damage after that incident and Villas-Boas was unhappy with Adam’s latest challenge.

In quotes reported by several national newspapers, Villas-Boas said: “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.”

The incident left Villas-Boas waiting to hear on the seriousness of Bale’s injury.

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.”

Bale’s appearance on Spurs’ United States tour had already caused controversy as he scored in the game with Los Angeles Galaxy on Wednesday despite having pulled out of the Team GB squad for the Olympics with a back injury.