Mikel Arteta claimed Arsenal must learn to shut out games if they are to propel themselves into a side capable of beating teams at the top of the Premier League table.
Jamie Vardy's 84th-minute goal salvaged a 1-1 draw for visiting Leicester City at Emirates Stadium on Tuesday, ending Arsenal's winning streak in the Premier League.
Victory would have lifted the Gunners, who took the lead through Pierre-Emerick Aubameyang in the first half but were disappointing after the break, into sixth place.
However, Eddie Nketiah's red card reduced the hosts to 10 men with 15 minutes remaining, and head coach Arteta was left to rue Arsenal's inability to put the result to bed.
"We have to learn. When you play against this opposition, when you have them, you have to kill them off," Arteta told reporters.
"That's the fourth time that we've had to play with 10 men. It's not possible for that long against this opposition. And I didn't like the goal we conceded.
"It's very difficult to do. The hardest thing to do is score goals. We generated the chances to go in with a much bigger margin at half time. If you don't do that you cannot play these games.
"I'm extremely proud of our team and the way we played against this type of opposition with how dominant we were in the first half.
"But clearly, we should've gone three or four-nil up and killed the game. That's what you have to do with this type of opposition."
Nketiah's dismissal came just four minutes after the 21-year-old had been introduced, and Arteta called on experienced forwards Aubameyang and Alexandre Lacazette to help the youngster learn from his mistake.
"He's disappointed," Arteta said. "He's on the front foot in every action and he didn't see the player.
"He needs to learn from this situation. They [Auba and Laca] will have to support him."
Arsenal's focus will now switch to Sunday's north London derby, with the match crucial for the Gunners' – and Tottenham's – European hopes.