Koscielny is set to be sidelined for six months, according to Wenger, bringing a sad end to his international career as he had planned to retire from international football after the World Cup in Russia.
The centre-back, who capped over 50 times for France senior national team, was carried off pitch 12 minutes into Arsenal’s Europa League semi-final second-leg defeat by Atletico Madrid last Thursday.
“He is of course devastated. He will be out for six months. You will not see him before the beginning of December at best,” Wenger told reporters.
Meanwhile, Koscielny told Evening Standard in May 2017 that he would require daily treatment on an Achilles injury for the rest of his career.
According to the newspaper, he was diagnosed with chronic tendonitis in both feet by the French Football Federation during an international break in October 2014.