London

Liverpool remain the team to beat in the Premier League as the champions swept aside big-spending Chelsea 2-0 on Sunday, while hopes of a title challenge from Manchester United were also undermined by Crystal Palace's fine win at Old Trafford.

The Eagles are one of five sides on maximum points at the top of the table, alongside Everton, Leicester, Liverpool and Arsenal.

Spurs were undone by Everton last weekend, but recovered in style as Son Heung-min and Harry Kane combined to thrash Southampton and round off an excellent week for the club after the return of Gareth Bale.

AFP Sports looks at three things we learned from the Premier League weekend.

Chelsea have created the biggest waves in the transfer market with a £200 million ($260 million) investment in players, but Liverpool showed the Blues need more than money if they are to dethrone the Reds as champions come the end of the season.

Frank Lampard insisted his side need time with only two of his five new signings fit to play and the expected arrival of a new goalkeeper in Edouard Mendy this week.

Another high-profile error from Kepa Arrizabalaga gifted Sadio Mane his and Liverpool's second goal, but by then the damage was already done.

Mane was the key figure as his run provoked Andreas Christensen's red card late in the first-half before the his header opened the scoring.

Whilst many of the chasing pack struggle with the tight turnaround of a short pre-season and bedding in new faces, Liverpool have stability in a title-wining team with one world-class addition in Thiago Alcantara.

The Spain midfielder made his debut as a second-half substitute and still completed more passes than any Chelsea player.

Manchester United started their season a week late due to their Europa League commitments last month and are still to get going after a dreadful display in losing 3-1 to Crystal Palace on Saturday.

Ole Gunnar Solskjaer pointed to a lack of match practice after just one friendly in a two-week pre-season but United knew the circumstances they faced weeks ago and are now already playing catch up, six points behind Liverpool.

Focus will also turn to United's lack of activity in the transfer market. While, Tottenham have brought back Bale, Liverpool added Thiago and Chelsea splashed out on an array of attacking talent, the Red Devils have made just one summer signing in Donny Van de Beek, who scored on his debut.

A failure to address areas of weakness at centre-back and left-back were badly exposed by Palace's pace on the counter-attack as Wilfried Zaha came back to haunt his old club by scoring twice.

While Tottenham fans have worked themselves into a frenzy over the loan signing of Bale, Son Heung-min and Harry Kane's combination in a 5-2 thrashing of Southampton showed Jose Mourinho will soon have a frightening front three to work with.

Bale isn't available until late October as the Wales forward recovers from a knee injury, leaving Son and Kane to shoulder the burden of leading the Tottenham attack.

That task won't be too onerous if they emulate the superb partnership that tore Southampton to shreds.

South Korea star Son bagged four goals, all of which were laid on by Kane, who notched Tottenham's fifth himself.

Together they have combined for more Premier League goals (24) than any other duo in the competition since August 2015.

"Son was on fire and for me Harry Kane was the man of the match, with what he did for the team," Mourinho said.