LIVERPOOL, England (AP) -- Roberto Firmino scored his first Premier League hat trick as Liverpool rallied to a 5-1 win over Arsenal to open a nine-point lead at the top of the standings on Saturday.
Liverpool bounced back in emphatic style to going behind in the 11th minute in another statement of intent as the team marches toward a first league title since 1990, and its 19th overall.
Firmino equalized with a trademark no-look finish from close range three minutes later, put Liverpool 2-1 ahead with a brilliant solo goal, and capped the victory with a spot kick in the 65th after regular penalty taker Mohamed Salah handed over duties to the Brazil striker.
In between, Sadio Mane and Salah -- also from the penalty spot -- scored as Liverpool capitalized on an inept defensive performance from Arsenal. It was the visitors' heaviest loss since Unai Emery took charge in the offseason and the tame display revived memories of some of the poorer performances in the latter years of predecessor Arsene Wenger's long reign.
Liverpool started the 20th round of the league with a six-point lead over second-placed Tottenham and that has been extended, with Spurs having unexpectedly lost 3-1 at home to Wolverhampton Wanderers earlier.
"I'm not the smartest person in the world," Liverpool manager Juergen Klopp said, "but I'm not an idiot. It's not important how far you are ahead in December."
Manchester City will climb back into second place if it beats Southampton on Sunday, but the gap to the leader would still be seven points ahead of their meeting at the Etihad Stadium on Thursday.
"It is a huge one," Liverpool defender Andrew Robertson said. "Everyone in the squad has been looking at it. But in December we've knocked the games off one by one and we've now got a healthy lead."
Liverpool is blowing away teams, with this ninth straight win coming three days after a 4-0 victory over Newcastle.
It didn't start off so well, though. Liverpool fell behind in the league at Anfield for the first time since Dec. 30 last year when Alex Iwobi crossed for Ainsley Maitland-Niles to slot home at the far post. That was only the eighth goal Liverpool has conceded in the league this season.
"We haven't conceded many," Klopp said, "so we didn't know what the reaction would be."
It was immediate and ruthless, exposing Arsenal's defensive frailties.
After Salah was tackled, an attempted clearance from Stephan Lichtsteiner hit teammate Shkodran Mustafi and ricocheted into the path of Firmino, who tapped in without looking at the ball.
The Brazil striker followed his first Anfield league goal in eight months with another 90 seconds later after Lucas Torreira was dispossessed by Mane. Firmino dribbled past weak challenges by Mustafi and Sokratis before shooting past Bernd Leno just as Torreira slipped while attempting a last-ditch tackle.
It was 3-1 in the 32nd when a simple long ball forward by Andrew Robertson went sailing over the head of Lichtsteiner, Salah played the ball across the face of the goal first time, and Mane stroked it into an empty net.
Salah got in on the act just before halftime and, just like against Newcastle, it came from a soft penalty when Sokratis clumsily barged into the back of the Egypt forward. Salah smashed his penalty down the middle, with Leno getting a slight touch.
Salah gave up penalty duties to allow Firmino to become the third Brazilian player to score a hat trick in the league, after Robinho and Afonso Alves. The decision was given after Sead Kolasinac pushed Dejan Lovren in the back following a free kick, and Firmino sent Leno the wrong way.
"I almost cried because we all know how much Mo wants to score goals," said Klopp, who described the gesture as "one of the nicest things I have seen in my life."