Champions League draw with Rangers in September 2010. However, Valencia made a breathtaking return to fitness and form within six months.
He played a key role as the Reds regained the Premier League title - making him a league champion for the first time - and he ended a topsy-turvy campaign with fittingly mixed emotions, starting his first Champions League final but tasting defeat against Barcelona.
Valencia's third season at Old Trafford proved his most eye-catching, as a glut of assists took United to within a whisker of a 20th league title, and his personal excellence was rewarded with a clean sweep at the club's end-of-season awards bash, where he picked up the fans' and players' player of the year gongs as well as the goal of the season award.
Michael Owen's departure in the summer of 2012 gave Antonio the chance to inherit the Reds' famous no.7 shirt, marking another lunge forward in the Ecuadorian's rise to prominence.
Perhaps the pressure of such a jersey weighed down on his considerably-sized shoulders as his consistency dipped slightly throughout the course of the season. However, like every top player, Valencia recaptured top form just at the right time,