On an evening when Alexis Sanchez, widely expected to leave at the season's end when his contract expires, made his first league start since his attempt to join rivals Manchester City, the striker continued to justify his club-record transfer fee.
The forward was unfortunate not to be awarded a penalty when brought down by Shkodran Mustafi's cumbersome challenge, but after returning to his feet he forced Petr Cech into a fine save when the goalkeeper tipped his low shot onto the post.
Mohamed Elneny, starting his first Premier League fixture since the season's opening day in perhaps a demonstration of Arsene Wenger's wariness of West Brom's physical threat, then briefly took responsibility for Arsenal's creativity.
On this occasion Ben Foster tipped Sanchez's curling effort away, but with the goalkeeper on the floor, Lacazette was the quickest to respond and instinctively headed low into the near open goal.
After Grzegorz Krychowiak broke down the left and hooked a cross towards the forward, Rodriguez succeeded in heading past Cech but could only watch as the recovering Nacho Monreal cleared off the goal-line and out for a corner.
- Arsenal 2-0 West Brom: Five talking points as Gunners winSkySports
- Alexandre Lacazette brace guides Arsenal to 2-0 home win over West Bromwich AlbionNewshub
- Arsenal 2 West Brom 0: Alexandre Lacazette scores a brace as Gunners survive ...Evening Standard
- Lacazette brace secures three points for Arsenal as Gareth Barry breaks ...Independent.ie
- Lacazette double extends Arsenal winning home recordRTE.ie
- Antonio Conte plans to return to Italy 'before long'Irish Times
- Football: Lacazette double takes spotlight from Barry milestone as Arsenal see ...The Straits Times
- Ref Watch: Should West Brom have been awarded a penalty against Arsenal?SkySports
- LISTEN: Monday Night Football Podcast featuring Jamie Carragher and Thierry HenrySkySports