"The manager was really upset at half-time, that's normal because it wasn't good enough for this football club," Spaniard Arteta said of Wenger.
"It was the angriest I have seen him."
The half-time rant failed to spark a recovery, with winger Sterling adding his second seven minutes after the restart before Arteta scored the consolation goal from the penalty spot after 69 minutes.
The loss saw Arsenal slip to second in the Premier League, one point behind Chelsea who beat Newcastle United 3-0, but Arteta was confident they were capable of picking themselves up and staying in the hunt for a first title since 2004.
He highlighted December's 6-3 thrashing by Manchester City, after which they won six of their next eight matches, a run that came to a sudden halt at Anfield.
"We have had two big crises already," the former Everton midfielder added.
"I think the Manchester United defeat was a different game to this, but City and this one are really hard to take. We have to react because there is nothing we can do about this now."
Wenger did not spare their blushes in public either, saying the performance was simply not good enough.
"We were feeble in every important aspect of playing at the highest level: concentration, strength in the challenge and naivety," he told French media.
"So from that moment on it's impossible to win a game when you're playing at that level."
He did, however, defend record signing Mesut Ozil, who came in for heavy criticism after match for a lethargic display in midfield.
"It is difficult to criticise an individual on this performance ... that would be unfair because nobody really played well."
(Reporting By Josh Reich; editing by Amlan Chakraborty)
