LONDON — Arsenal manager Mikel Arteta has revealed that Martin Odegaard’s significant ankle injury will rule him out of action for a while. The Arsenal captain limped off during Norway’s Nations League win over Austria on September 9 after twisting his left ankle. He required the help of physios before leaving the pitch to receive further treatment. Odegaard, 25, then returned to London for an MRI scan and missed his side’s win in the north London derby against Tottenham Hotspur. “After everything was scanned, they showed that there was some damage, especially in one of the ligaments in the ankle so we’re going to miss him. I don’t want to (put a timeframe on it) because I am not a doctor but it is something quite significant so we’re going to lose him for a while – hopefully not months but let’s see,” Arteta said in press conference ahead of facing Atalanta in the Champions League on Thursday. The Gunners captain is essential to the team’s performance. Finding a replacement for the Norwegian, who finished the previous season with 11 goals and an equal number of assists, will be a challenging task. “He’s our captain. He’s one of our biggest...