Chelsea striker Fernando Torres has suffered a knee injury that will sideline him for some three weeks, the Premier League club announced on their website on Wednesday.

The 29-year-old Spain forward underwent a scan at Chelsea's Cobham training base after limping out just 11 minutes into Tuesday's Champions League 4-0 group victory away to Romania's Steaua Bucharest.

"Chelsea Football Club can confirm Fernando Torres suffered a medial collateral ligament injury to his left knee in the Champions League group game at Steaua Bucharest on Tuesday evening," the statement issued by the west London club said.

"The 29-year-old will be out for approximately three weeks."

Torres, already due to miss Sunday's Premier League match at Norwich after collecting two yellow cards in a 1-1 draw with Tottenham Hotspur, was ruled out Tuesday of Spain's forthcoming World Cup qualifiers against Belarus and Georgia.

Tuesday also saw England's governing Football Association announce that Torres would not face additional punishment for clawing at at the face of Spurs' Belgian defender Jan Vertonghen at White Hart Lane last weekend because the incident was seen, in part, by one of the match officials.

The FA's inaction prompted a stinging response from Tottenham manager Andre Villas-Boas, who accused officials of a "disgrace" of a decision and acting in "farcical" fashion.

"Obviously, it is almost a farcical decision," Villas-Boas said Wednesday, with the Portuguese adding: "I think the FA has made a decision almost a joke. It looks incredible.

"How can you see the images, pretty clear, and come out without punishment, on something (which) overtakes all professional behaviour?

"I think the decision is a disgrace."

Later in the same match, Torres was sent off for receiving two yellow cards, meaning he will serve just a one-match ban.

This season has seen the FA introduce a new system where three former referees will look at incidents retrospectively and decide if charges should be brought.

Previously, action was only taken if the match referee viewed the footage and judged whether he should have in fact sent a player off.

However, in both cases if any match official saw some of the incident, even if not in its absolute entirety, then the FA cannot take further action.