Walcott Joins Casualties

Wayne Rooney's return from injury may come even earlier than previously imagined, with Sven-Goran Eriksson contemplating playing the forward off the bench against Trinidad & Tobago in Nuremberg on Thursday. Eriksson's hand may be forced after his youngest wunderkind, Theo Walcott, reported a calf injury yesterday, ironically after being "smashed" from behind by Wayne Rooney in training.

Walcott's right leg had to be heavily bandaged and although he is expected to resume training tomorrow he will need close monitoring if he is to be available for Thursday's match. Eriksson is confident that the 17-year-old Arsenal reserve will recover but the injury scare exposes the fragility of England's squad and, in particular, the lack of choice when it comes to attackers.

Eriksson's optimism has been stretched a lot recently but it appears still to be holding strong - especially where Rooney is concerned. "We have to decide on Rooney day by day, to be honest. I'm very optimistic, always. I will change something in the team if we have some problems," he said.

Eriksson had described his omission of Jermain Defoe, Andrew Johnson and Darren Bent as a "gamble" and, as it stands, he now has only one fully fit striker in the far-from-prolific Peter Crouch.

Behind Crouch there are only Walcott and two convalescents in Rooney and Michael Owen, whose poor performance against Paraguay on Saturday highlighted that he is still well short of his optimum fitness. There has already been fierce criticism of Eriksson's inclusion of only four forwards in his 23-man party but the England head coach could never have envisaged the chain of events that led to Walcott being strapped up yesterday.

It is not certain that the injury was caused by Rooney but in his determination to take part in full-contact training the Manchester United striker was seen clattering into Walcott from behind as the unused substitutes from Saturday's victory over Paraguay went on to the pitch after the game for what was to be a gentle work-out.

Walcott was able to take part in a light training session yesterday but afterwards complained that his calf was sore and he was examined by the team doctor Leif Sward and the physiotherapist Gary Lewin. It is unclear whether he had taken another blow to the same area.

What is clear is that in their five-a-side games the players are instructed not to make what Eriksson describes as "stupid challenges". Rooney operates by different rules. He is notorious among his England and United team-mates for flying into tackles in practice and, perhaps over-eager to prove his fitness, it was a typically robust challenge that flattened Walcott. Lee Sharpe, the former England international, was among those watching the players in Frankfurt's Waldstadion.

"Rooney seemed to be moving well, doing lots of slalom and shuttle runs and booting the ball around," he said on a blog for Yahoo. "He didn't seem to be holding back and at one stage they were doing five-a-side and he smashed Walcott from behind."

"Theo has a slight knock and it has been strapped up for compression purposes," the FA confirmed. "It's precautionary and after a day off on Monday he will take part in our next training session on Tuesday." Walcott will undergo medical tests today to ascertain whether he can resume full training or whether he will be restricted to light jogging.