Albion made six changes to the team that drew at West Ham and started the match brightly against an Arsenal team off the back of a 3-1 victory against Chelsea on Boxing Day.
As so often this season though Brighton failed to convert good play and pressure into goals and sure enough Arsenal improved after the break and took their chance.
Bukayo Saka was impressive and it was his run and cross that teed-up second half substitute Lacazette who scored the winner with his first touch on 66 minutes.
Scroll down and click through to see how Graham Potter's players rated and who struggled.
Bukayo Saka was impressive and it was his run and cross that teed-up second half substitute Lacazette who scored the winner with his first touch on 66 minutes.