LONDON  -  Jurgen Klopp warned much tougher challenges lie ahead of Liverpool's quest to end a near three-decade wait to win the Premier League after brushing aside West Ham 4-0 at a jubilant Anfield on Sunday.

Mohamed Salah opened his account for the season, Sadio Mane scored twice and Daniel Sturridge added a late fourth in an impressive display by Klopp's men as £65 million ($83 million) goalkeeper Alisson Becker kept a clean sheet on debut. Liverpool haven't been crowned champions of England since 1989/90 and finished 25 points behind City last season. But after reaching the Champions League final in May and spending more than anyone else in the Premier League in the off-season, there is palpable belief that wait will come to an end in May. 

There was little tinkering for Klopp to do up front after Salah, Mane and Roberto Firmino combined for 91 goals last season, and they again provided the firepower to outclass a sorry West Ham despite their own near £100 million outlay on nine new players. Salah and Mane's pain at international level was Liverpool's gain as early exits at the World Cup with Egypt and Senegal meant they could join the club's pre-season tour of the United States, unlike a host of Premier League stars who returned to training just last week after their exertions in Russia.

A revelation in his first season at Anfield with 44 goals in all competitions, Salah is now a marked man. Yet, he was given the simplest of tasks to tap home the opener into an empty net on 19 minutes from Andy Robertson's pinpoint cross after he was freed down the left by the impressive Keita.

Salah should have had more as he was well picked out by a bursting run by Firmino only to place his shot too close to Lukasz Fabianski, who also made a brilliant save to turn Trent Alexander-Arnold's free-kick behind. Fabianski was by far the busier 'keeper with Alisson making just one comfortable save and impressing far more with his feet to launch a series of Liverpool attacks.

The hosts finally doubled their lead to give the score the half-time reflection it deserved when another teasing Robertson cross was pulled across goal by James Milner and Mane left unmarked to side-foot home. Mane produced a fine finish for his second eight minutes after the break after good work by Firmino, but had the linesman to thank just as much for the assist as he somehow wasn't flagged offside before firing past Fabianski.

STYLISH CITY SPOIL EMERY'S ARSENAL BOW: Manchester City ruined the start of the Unai Emery era at Arsenal as the champions signalled their intent to retain the Premier League title with a stylish 2-0 win on Sunday. Pep Guardiola's side swept to the title last term with a record 100 points and they were quickly back in the groove at the Emirates Stadium.

Raheem Sterling opened the scoring with a clinical finish early in the first half and Bernardo Silva's thunderous strike capped a City success that served as a resounding warning to their title rivals. No team has successfully defended the English title since Manchester United in 2008-09. But on the evidence of this composed display, City have every chance of emulating their rivals' achievement.

Picking up where they left off last term, City had too much class for Arsenal and easily repelled the hosts' few dangerous moments. "We played at a high level. We created a lot of chances. We are satisfied for many reasons," Guardiola said. "In the first half we deserved to score two or three more."

City's excellence underlined the size of the task facing new Arsenal boss Emery as the Gunners begin life without Arsene Wenger.

Arsenal were playing a competitive match without Wenger in charge for the first time since September 1996.

Emery was hired to replace Wenger following the Frenchman's exit at the end of a dismal campaign which saw Arsenal labour to a sixth-place finish in the Premier League -- 37 points behind City.

The Spaniard will need time to make his mark on a moribund club and, while Arsenal couldn't be faulted for effort against City, there was precious little quality about their play.

"We wanted to show our best performance, but the first half we didn't play like we wanted. We spoke at half-time about taking more responsibility," Emery said.

Guardiola started with Kevin De Bruyne and Leroy Sane on the bench as he recalled Sterling and gave a Premier League debut to Algeria winger Riyad Mahrez, whose move from Leicester was Guardiola's only major close-season signing.