And United manager Sir Alex Ferguson is able to breathe a sigh of relief that the youngster's injury is not as severe as was first feared.

Possebon was left in agony following a challenge from Middlesbrough captain Emanuel Pogatetz as United recorded a 3-1 victory at Old Trafford on Tuesday night.

Possebon was later given the all-clear after spending the night in hospital.

"We can confirm that Rodrigo did not suffer a break to his right leg," a United spokesperson told manutd.com.

"He was kept in hospital overnight for observation and to assess whether there was any ligament damage to his knee."

Speaking following the match, Ferguson had revealed his shock at the challenge which occurred midway through the second half.

Even Middlesbrough manager Gareth Southgate admitted he could have no complaints at the red card which was instantly shown to Pogatetz.

Possebon needed oxygen on the pitch and was then taken straight to hospital for further treatment, with Ferguson at the time knowing there could be bad news to come on the 19-year-old Brazilian.

"You don't want to see things like that and I hope I never see anything like it again," said the United boss.

"It is such a pity for the boy and took the gloss off what was a really good performance.

"The thing that gets me about challenges like that is that the opponent always claims he has done nothing wrong.

"He [Pogatetz] should have just walked off the field. Then you get their bench screaming that it wasn't a sending off and there is nothing wrong with our player.

"At least Gareth Southgate was very good about it. He apologised and understood the gravity. It was an absolutely terrible tackle."

Boro manager Southgate branded the challenge "poor" and admitted members of his bench had stepped out of line.

"A couple of lads on our bench did not have the same view as I did but that is dealt with now," he said.

"We can have no complaints about the decision. It is difficult to know why it happened.

"It was an unusual aberration for him because his discipline has improved in the last two years."