The 21-year-old France international was heavily linked with a move to The Emirates throughout the summer window but a transfer failed to materialise for the attacker.
Arsenal were widely reported to have made a late bid-money bid to try and bring the attacker to north London just before the transfer window closed at the end of last month.
However, the Gunners failed to secure a move to land the midfielder from Monaco before the deadline.
Arsenal were reported to be interested in signing Lemar shortly after Alexandre Lacazette joined the Gunners from Lyon back in July.
And BBC reporter Ornstein claims that Lemar made it clear he would be happy to sign for the Gunners back then, but could not confirm claims that he had even visited the club’s London Colney training ground.
Ornstein said on Arsenal podcast Arseblog: “The messages I was getting was that the interest in Lemar was absolutely concrete.
“They were hoping to make him their next signing [after Lacazette], but it wasn’t close at that point. Monaco weren’t interested in selling.
“Although, he had given indications, as I understand it, to Arsenal that he was prepared to join at that point.
“Lemar visiting the training ground? I know nothing of that.
“I’m not saying it’s not true but it’s certainly not been told to me by anybody.
“I have seen those reports and I fully respect them but I just can’t verify them myself.
“But what I have been told, reliably by a number of people, is that he had told Arsene Wenger that he wanted to, and was prepared to, join at that time.”
Arsenal return to Premier League action on Saturday with a home clash against Bournemouth at The Emirates.
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