When it comes to Manchester United legends, there aren't many bigger than Sir Alex Ferguson.Actually, scratch that, there are none bigger than the greatest manager the sport of football has ever seen.Ferguson's historic 26-season reign in Manchester was littered with trophies and it's why a stand at Old Trafford is named after him.The Scotsman is now 81 years of age, but still regularly travels to watch his beloved United side.Ferguson was in the Old Trafford crowd on Saturday evening to get a glimpse of Erik ten Hag's men in action against Reading in the FA Cup fourth round.But like many others watching in the stadium and indeed around the world, the football icon wasn't thrilled by what was unfolding on the pitch during the first half.The opening 45 minutes of play between United and Reading was poor at best.In fact, it was so poor that Ferguson decided to have a quick nap up in the stands, with the cameras catching him just before Marcus Rashford had a goal disallowed for offside by VAR.
Video: Ferguson was caught asleep during Man Utd vs Reading
Fair play, Sir Alex.
The man is 81 and a bona fide sporting great, so he can sleep when he goddam wants - a take which many United fans on social media agree with.
Thankfully in the second half at Old Trafford, there was action aplenty to keep Ferguson and the rest watching entertained.
Summer signing Casemiro scored a brilliant double in the space of three minutes. The first was a cool finish after a sublime pass from Antony, while the second was a cracking strike from distance.
Yes, it may have taken a little deflection off a Reading player, but take nothing away from the five-time Champions League winner - who's already proving to be one of United's best signings of the 21st century.
Video: Casemiro's second goal vs Reading
Well played, Casemiro.
Shortly after Casemiro made it 2-0, veteran striker Andy Carroll was shown a second yellow card for a wild tackle on the Brazil international.
Goals then continued to flow. Substitute Fred made it 3-0 with an inventive finish, before 10-man Reading surprisingly reduced the deficit courtesy of a powerful header by Amadou Mbengue.
The match eventually finished 3-1 to United, which means they will be in Monday's FA Cup fifth round draw.
Premier League quiz: Can you name these 40 players from the 2010s?
You can find all of the latest football news and rumours right here.