The 33-year-old has not completed 90 minutes since the end of last season and missed last summer’s World Cup with the injury, but Arsenal’s centre-back crisis is likely to see him returned to the fold for next weekend’s trip to Southampton.
Leno, who joined Arsenal from Leverkusen for £19.2 million last summer, is looking forward to playing with a man who he says has managed to lead and inspire even while out of the side.
Revealing that Koscielny made a speech to the Arsenal squad ahead of last weekend’s north London derby, Leno said: “Before Tottenham he was not in the squad, but five minutes before the game he said many, many good things about the history of the game, how important it is for the fans, for the club, for every player.
“He is the perfect captain for us. In training, you see how he is talking to other players. We have many young players and he talks to them, and for me he is a big personality in the team, in the dressing room.”
In an ideal world, Koscielny would probably have been given an extra week or two to feel his way back to full fitness, but circumstances have forced Emery’s hand.
Shkodran Mustafi and Sokratis Papastathopoulos both picked up one-match suspensions in Saturday’s 1-0 win over Huddersfield Town, leaving Arsenal with no fully-fit specialist centre-backs after Rob Holding’s season-ending cruciate ligament injury against Manchester United on Wednesday.
Stephan Lichtsteiner and Nacho Monreal can both deputise in central defence, and those two, along with Koscielny, will have to get by for now, starting with Thursday night’s Europa League dead rubber against Qarabag.
“He is a big personality and of course he has big quality,” Leno said of Koscielny. “We should give him time. The coach is calm with him, because he was for a long time injured.
“I am happy for him that maybe he will play. I think he will play, because he needs the confidence. His body also needs the feeling for the game.
“Of course, he has trained for a long time. But games are more difficult, because the game is different for your head. He will maybe start on Thursday, and of course he will be an option for the next weeks.”
Leno praised the mentality of the Arsenal squad after they extended their unbeaten run to 21 games, stressing the battling qualities that served them particularly well against Huddersfield.
“It gives us confidence because we knew that it would be a hard game against Huddersfield,” Leno added. “Of course, we have quality but it was not the quality [that won Arsenal the game]. The most important thing was our mentality.”
Lucas Torreira’s 83rd-minute winner secured all three points for the Gunners, keeping them on track for their stated objective of a return to the Champions League.
“Now we are 21 games unbeaten but it is not the most important thing,” Leno insisted. “The most important thing is that we won a game.
That maybe could be the result that helps us get into the top four, and that’s what we need.
“The goal came less than 10 minutes before the end of the game so we needed to be calm, to play our football, don’t lose possession too easily.
“We waited for our chance and, of course, it was quality in the end from Torreira, but I think it was more about our mentality.”
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