Valencia, 25, has missed the majority of the season after suffering a double fracture in his ankle during a Champions League clash with Rangers in September.
But the Ecuador wide-man returned to action in the FA Cup victory over Arsenal on March 12, and followed up an impressive appearance from the substitutes' bench with another against Marseille three days later to help United move into the Champions League quarter-finals.
And after playing 90 minutes in United's last outing against Bolton and 75 minutes in Ecuador's 2-0 defeat to Colombia on Saturday, Valencia's return has come at a perfect time for his club as they prepare to fight on three fronts in a busy run-in, with Ferguson delighted with the former Wigan man's progress.
"Antonio has showed in the parts of the games he's played so far why we've missed him,'' Ferguson told Inside United. "He is a fantastic footballer. He came on at the right time against Marseille because Nani was starting to wilt a bit after his injury.
"His ability to get to the dead ball line is a big advantage to us and his football brain was there for all to see when he made Javier Hernandez's second goal against Marseille. His pass to Ryan Giggs was fantastic.
"It is a big plus point. Having both Antonio and Nani is a big boost for us.''