Arsenal had been outplayed up to that point but managed to hold on for the rest of the game to secure a point, though their manager was visibly angry at how Pepe had left his team-mates in a tough position.
“It’s unacceptable,” Arteta said, adding that the Ivory Coast international had “let down” his team-mates.
The Spaniard’s mood was not helped by a muscular injury to Willian that forced the Brazilian’s withdrawal at half-time, while substitute Bukayo Saka came off worst in a challenge late on and limped off.
Although they were able to thwart a wasteful Leeds, Arsenal offered little going forward and they have scored only once in their most recent five Premier League matches.
Captain Pierre-Emerick Aubameyang was largely isolated after being given a rare chance in a central role up front, with Alexandre Lacazette dropping to the bench as the Gunners had just two shots on target on Sunday afternoon.
“The fact we need to score more goals, it’s a concern,” Arteta said. “We need goals and a lot of goals to win football matches to be the top team that we want to be. Without that it is impossible.
“It doesn’t matter how we are defensively. It’s not the lack of attacking players we have or the attacking players we are putting on the pitch, but we need some moments where we have to make better decisions and be more ruthless.
“But it’s the most difficult thing in football and sometimes we go through these patches and we have to overcome. I have to help the players to overcome and do it as quickly as possible.”
While Arteta was dissatisfied at leaving West Yorkshire with only a point, he was able to take some positives.
“We have to take a point considering the circumstances,” he added. “I’m never satisfied with a point but we know that the challenge that we faced in the second half for 40 minutes in the second half with 10 men.
“The way we reacted to it and the resilience that we showed, the effort that all the players put in to try to overcome that advantage was phenomenal.”
Leeds had 25 attempts at goal – 13 in the first half and 12 after the interval – but only four were on target on a day where Rodrigo, Patrick Bamford and Raphinha – handed his first start for the club – all hit the woodwork.
Marcelo Bielsa lamented an inability to capitalise on their chances but when it was put to him that it is a mark of how far Leeds have come that a draw with Arsenal is considered disappointing, the boss said: “Perhaps it’s how you say.”
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