UNITED defender John O'Shea has been sent back to the Reds to avoid further damage to his calf.
Trapattoni said the decision had been taken in an effort to prevent the damage from getting any worse and incurring a lengthy lay-off.
He said: "Today, he could not play because he had a bleed on the calf. He couldn't run today.
"I told him to be careful because when you pull that muscle, it is two months.
"It was not just for me, it was also for the club he must decide."