Pierre Aubameyang fired a brace as Arsenal overwhelmed Norwich at the Emirates Stadium.
The striker took his Premier League tally to 19 goals for the campaign, with Granit Xhaka also on target for the Gunners.
Cedric Soares lashed in a late goal on his debut for Arsenal.
Norwich threatened at times but a porous defence remains their Achilles heel as Aubameyang was twice teed up by opposing players, either side of laying on Xhaka's goal.
Aubameyang's first goal, handed on a platter by Norwich goalkeeper Tim Krul, saw him reach 50 Premier League strikes in just 79 appearances, the fastest Arsenal player to reach a half-century.
Krul dawdled in possession and struck his clearance straight at Aubameyang, who tucked home into an empty net.
Four minutes later Kieran Tierney and Aubameyang combined before the latter fed Xhaka, who hit his first league goal in almost 14 months.
Chasing the game, the Norwich were left incensed when ref Peter Bankes and the VAR decided that Sead Kolasinac had not fouled Todd Cantwell inside the box.
A Norwich throw-in inside their own half was sent towards sub Josip Drmic, who opted to send the ball back into the Canaries' penalty area and straight to Aubameyang - the Gabon striker more than happy to oblige in finishing for his second of the night. The gloss was applied by Soares.
Premier League: Arsenal 4 Nowich City 0