Arsenal: Mikel Arteta confirms new injury worry as Gabriel and Gabriel Martinelli substitutions explained

Copley received treatment from the Arsenal medical staff, and required assistance in being helped back to his feet as he was replaced by Theo Julienne before heading straight down the tunnel.Arteta, speaking after the 3-1 loss, confirmed the 19-year-old is set to undergo a scan on Thursday to determine the severity of the injury, with the Arsenal boss hopeful of some positive news.He said: “Well, probably we're going to have it tomorrow. It doesn't look good, the mechanism is not too positive, the symptoms that he already has either.“So let's hope that tomorrow the news is better.”Louie Copley had to be helped off the pitch by Arsenal’s medical staffGettyCopley was one of seven Arsenal half-time substitutes against Real Betis, alongside Gabriel and Gabriel Martinelli as the pair made their first appearances of the summer following an extended break due to the World Cup.Like Copley, the Brazilian duo also did not finish the second half as they were withdrawn with a quarter of the game to go.With the Gunners back in action against Borussia Dortmund this Sunday, it’s likely that Gabriel and Gabriel Martinelli will each get a 45 minute run-out at the Emirates Stadium.