Campbell, who returned to the Gunners this summer after his loan spell at Olympiakos, is staking his claim for a regular spot in Arsene Wenger’s first-team.
The Costa Rica international was in fine form at Emirates Stadium as he played the full 90 minutes, despite failing to get on the score-sheet.
Midfielder Diaby, meanwhile, played the first half before being replaced by Gedion Zelalem at half-time.
Also in action for the Gunners were Isaac Hayden, Hector Bellerin and Chuba Akpom, as Arsene Wenger watched on from the stands.
Daniel Crowley netted the opener in the second minute, before Akpom’s hat-trick wrapped up the victory.
Here are some of the best photos from Thursday’s game.
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