Arsenal's record signing Pierre-Emerick Aubameyang made a scoring debut and Henrikh Mkhitaryan provided three assists on his first start having joined from Manchester United.
But Aaron Ramsey seized the limelight from the January recruits by scoring a hat trick as Arsenal crushed Everton 5-1 in the Premier League.
It was an emphatic response from Arsenal to losing at Swansea 3-1 a day before Aubameyang joined from Borussia Dortmund for $110 million.
Aubameyang dinked the ball over goalkeeper Jordan Pickford for Arsenal's fourth in the 37th minute after being set up by Mkhitaryan.
Ramsey had already netted twice by that stage either side of Laurent Koscielny's strike. Ramsey completed his treble in the second half from Mkhitaryan's cutback, and Dominic Calvert-Lewin headed in a consolation.
Arsenal are five points from the four Champions League places in sixth place, while Everton are 10th.