The forward has impressed for Arsene Wenger's side this season.
The Costa Rican has found himself as a first team regular this season, with injuries to the likes of Theo Walcott and Alexis Sanchez giving him his chance to shine.
He has done just that, with a series of impressive displays leading to praise from a number of sources, including manager Arsene Wenger.
And he says that his recent upturn in form is solely down to him having increased confidence to give more every time he plays.
“I think I have improved in my confidence, which I believe is the most important thing for a player," he told arsenal.com.
After every game I have played on the pitch, I have felt even more comfortable. So I feel very confident about what I am capable of and that gives me a lot of calmness.”
“I try to give my best, to run as much as I can, to score and to help the team in everything they need, so that would make it easier to be considered for the next match.”
The problem for Campbell now will be finding regular game time in the second half of the campaign.
He has flourished while several stars have been out with long-term injuries, but they are all now returning, meaning he is likely to find himself down the pecking order again.
However, he has certainly offered enough to suggest he should be ahead of the likes of Alex Oxlade-Chamberlain, and he will be hoping Arsene Wenger will call upon him again in the Gunners’ remaining games.