Manchester United today, became the first of the Premier League’s top five of last season to taste defeat in the new campaign as poor defending tactics saw Jose Mourinho’s men defeated 3-2 by Chris Hughton’s Brighton & Hove Albion F.C. on Sunday afternoon.

Threatening for the Red Devils, their arch-rivals and defending champions look in no mood to be caught as Pep Guardiola’s Manchester City men thrashed Huddersfield Town to a 6-1 victory, while Chelsea and Tottenham Hotspur maintained their perfect starts to the week.

Here, Football Weeks have highlighted five things learned from the Premier League weekend:

No case for United’s poor defence

Mourinho’s pre-season predictions statement on if he wasn’t given the funds to strengthen his defence, there would be a doom actually came true in a disastrous first 45 minutes at Brighton.

The Portuguese boss main priority was to strengthen his central defence, but funny enough, today’s fault came from the two centre-backs (Victor Lindelof and Eric Bailly) signed by Mourinho in a combined £60 million last summer.

Lindelof left Glenn Murray unmarked for the Seagulls opener, while Bailly on the other hand, chopped down Pascal Gross to concede a needless penalty just as United had got back into the game thanks to Romelu Lukaku’s header.

Mourinho in his post match conference, said:

“We made incredible mistakes in some crucial moments. Mistakes that killed us.”

Jorginho – Is Chelsea’s new commander in chief

Had it been Manchester City who won the race to the signing of Jorginho this summer, the defending champions would be even more of a terrifying prospect. Instead, Jorginho has been charged with helping his former boss Maurizio Sarri command a fine balance of possession and pressing that showed their time together at Napoli with Chelsea.

The Italy international showed glimpses of scintillating performance in midfield as Chelsea cruised Arsenal to 3-2 victory at Stamford Bridge.

Jorginho v Arsenal
Chelsea’s Jorginho and Pierre-Emerick Aubameyang tussle for the ball

As Jorginho showed sign of wilt in midfield, so did his side which saw Arsenal roared back from 2-0 down to level just before half-time in a 15-minute thriller.

The half-time break came handy for Chelsea as it helped Jorginho regained fuel in the second period to help Chelsea secure their two first two wins under Sarri.

Despite predicted World Cup fatigue, Spurs’ World Cup stars make waves

Pep Guardiola suggested World Cup fatigue may have played a huge role in a knee injury to Kevin de Bruyne that is likely to keep the midfielder out for three months, but Tottenham, who had more players at the tournament, are making waves despite barely a week of pre-season training.

Tottenham’s players, than any other Premier League club, logged more minutes in Russia and while the fatigue may yet undermine a title challenge, Mauricio Pochettino’s men have put their off-field troubles in the transfer market and delays in the completion of their new stadium to one side with a strong start to the season by beating Newcastle United and Fulham.

Kieran Trippier repeated his World Cup heroics with a stunning free-kick and Harry Kane ended his August hoodoo to send Spurs in fine fettle for a huge clash at Manchester United next Monday.

Sergio Aguero and Guardiola revived ?

Gone are the days when Pep Guardiola would prefer leaving City’s all-time top scorer Sergio Aguero on the bench ahead of Gabriel Jesus.

Aguero scored his ninth Premier League hat-trick in City’s 6-1 annihilation of Huddersfield at Etihad Stadium on Sunday afternoon.

The Argentine’s goalscoring ability was never in doubt, but this is an improvement in his all-round game under Guardiola which has won over the former Bayern Munich and Barcelona coach.

On this remarkable performance, Guardiola said:

“He feels free now. He just doesn’t score goals, he makes space and doesn’t stop and when he does that, he’s one of the best strikers in the world.”

It’s no surprising Guardiola sealed this with a kiss on Aguero’s cheek when he came off to a standing ovation at 76′ minute for Leroy Sane.

More woe at West Ham despite PL winning coach & £100m investment

There’s no denying West Ham United fans would be hoping for a turnaround at London Stadium with a near £100 million investment on nine players and a Premier League winning coach after a poor outing on and off the field last season.

Instead, there has been no immediate return on this investment as a 4-0 opening weekend mauling at Liverpool was followed by a 2-1 home defeat to AFC Bournemouth.

Jack Wilshere is one of the faces at West Ham who is so far yet to live up to expectations and admits the Hammers need to find their best performance under Manuael Pellegrini before his visit to Arsenal next weekend.

The former Arsenal midfielder said:

“We have got a lot of new players and we need to gel.

“At this level in this league, people aren’t given time, so we have to do it quick and all tuck in this week.”