The Costa Rica international was a key part of his country’s success after the Central American topped Group D ahead of Uruguay, Italy and England this summer.
Campbell returned to the Gunners this season as the 22-year-old attempts to forge an Arsenal career after a series of loan spells, although the north London club reportedly blocked a deadline day move to Benfica.
“Playing at the World Cup was the best experience of my life so far,” Campbell told Arsenal’s website.
“The World Cup is something unique. My team-mates and I worked really hard and made history for our country. We are really happy about that.
“What we did was a milestone for us. We wanted to make history, we wanted to exceed the last 16 that Costa Rica reached at the 1990 World Cup. This year we reached the quarter-finals and that will mark a turning point in our history.
“It was a confidence booster for me. If the Costa Rican national team keeps up the good work we will stay up with the best teams. I learnt that a Costa Rican player could compete with the best in the world. We all have to keep on proving it.”
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