US Edition Valencia was stretchered off on Tuesday during United's Champions League 0-0 draw with Rangers after suffering an horrific injury following an innocuous incident involving Kirk Broadfoot.
Initially, Ferguson said Valencia would miss the remainder of the campaign. However, it now appears the damage is not quite as bad as the United manager feared.
''You can never be 100 per cent accurate in these situations and it is a bad injury, but we are looking at the end of February, which is better than we thought on Tuesday,'' said Ferguson.
Valencia had an operation on Wednesday evening to put his left ankle back into place after it was fractured and dislocated.
Ferguson revealed the Ecuador star had also suffered some ligament damage.
"The operation has been successful and the break was clean, which was the major concern for us at the time," he said. "He is a strong boy, who is very positive about it.
"Being positive helps you in these situations, so we are very hopeful we will get him back then."
Ferguson, who has no other injury concerns ahead of Sunday's duel with Liverpool at Old Trafford, accepts the loss of Valencia is a significant blow.
However, in Nani, Ryan Giggs and Park Ji-sung, plus to a lesser extent Gabriel Obertan and new-boy Bebe, who made his reserve team debut last night, he feels United have the options to cope.
"It is a blow losing good players but in the context of the kind of squad we have, we should be able to cope with it.
"But having players like Nani, Ryan Giggs and Park Ji-sung, plus Gabriel Obertan and Bebe means we have options."