It appears nine goals in 13 appearances isn’t quite enough to keep the critics off Pierre-Emerick Aubameyang’s back.
Aubameyang spurned a number of chances after coming on for possible leg-break victim Danny Welbeck during the Europa League stalemate.
But despite a difficult night for a number of reasons, Keown wasn’t in the mood to allow the Gabon international, 29, any excuses.
“Aubameyang let Arsenal down,” Keown said on BT Sport. “He is the closest thing to Thierry Henry since he left that club. He really is that good. And someone should really be in his camp pushing him on.
“Dragging him, drawing a performance out of him. Because he’s a special talent, scores lots of goals and it’s just a hunger.
“It’s getting to that boiling point and I don’t think he was there tonight.”
The £56 million striker may be able to get his goal ratio up with Welbeck’s season now hanging in the balance.
Manager Unai Emery said: “We think it’s a serious injury.
“Every injury is different. He broke something in his ankle and it’s a different injury than another.
“Now he’s at the hospital and the news is at the moment we are going to wait, but we think this is a serious injury.”