23'
Arsenal scored twice in each half to earn a third straight Premier League victory, beating West Bromwich Albion 4-0 at The Hawthorns.
The Gunners started the match strongly and took the lead through Kieran Tierney's fine solo goal, the defender beating Darnell Furlong before cutting inside and finding the top-right corner.
Matt Phillips stung the palms of Bernd Leno before Arsenal doubled their advantage with 28 minutes on the clock.
Emile Smith Rowe squared for Bukayo Saka to tap in from close range after a slick passing move involving Alexandre Lacazette.
Lacazette then pounced on a loose ball on the hour mark to score for the third match in succession, before converting Tierney's cross to double his tally four minutes later.
Having built on wins over Chelsea and Brighton & Hove Albion, Arsenal move up to 11th place with 23 points.
West Brom remain 19th, six points from safety.
See: West Brom report | Arsenal report
Next fixtures
West Brom: 16 Jan v Wolves (A)
Arsenal: 14 Jan v Crystal Palace (H)
Match officials
Referee: Martin Atkinson. Assistants: Constantine Hatzidakis, Harry Lennard. Fourth official: Darren England. VAR: Jonathan Moss. Assistant VAR: Stephen Child.
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