Manchester United started their Premier League season on a high following an impressive 5-1 thrashing of old rivals, Leeds United on Saturday at Old Trafford.
Bruno Fernandes registered his first hat trick of the season after he got on the end of a through ball from Paul Pogba on 30 minutes to score his first goal through the legs of Illan Meslier.
Leeds got back into the game three minutes into the second half with a stunning strike from Ayling.
It took United just three minutes to restore their lead, however, after launching a counter-attack, Pogba found Greenwood who ran down the left wing and worked the ball into the net.
Fernandes got his second on 54 minutes. It looked like Ayling had cleared the ball off the line but referee Paul Tierney got the signal on his wrist watch that the ball had crossed the line.
The Portugal international completed his hat trick — his first since joining United — on the hour mark with a powerful strike past Meslier.
Pogba secured his fourth assist on 68 minutes when he squared a ball for Fred who hit it into the net from 10 yards out.
In the other game played yesterday, Arsenal were soundly beaten 2-0 by newly-promoted side Brentford, as goals from Sergi Canos and Christian Norgaard condemned the Gunners to Premier League defeat on the first day of action at Brentford Community Stadium.