Manchester United suffered a miserable start to their Premier League campaign as Wilfried Zaha fired Crystal Palace to a shock 3-1 win at Old Trafford, while Leeds beat Fulham 4-3 to earn their first top-flight victory since 2004 on Saturday.
On the second weekend of the new campaign, United were playing for the first time after being given an extra week of rest due to their involvement in the latter stages of last season's Europa League.
But Ole Gunnar Solskjaer's lethargic side were well below their best and Palace took full advantage thanks to Andros Townsend's seventh minute strike and Zaha's 74th minute penalty against his former club.
There was a hint of controversy about Zaha's goal as VAR ruled Victor Lindelof had handled Jordan Ayew's shot even though the ball was hit with force at him from close quarters.
David De Gea saved Ayew's spot-kick, but VAR intervened again to order a retake as United's keeper had strayed off his line and this time Zaha converted from the spot.
United's only major close-season signing Donny van de Beek came off the bench and the former Ajax midfielder reduced the deficit with a debut goal in the 80th minute.
But Zaha, who endured a difficult spell at United before rejoining Palace, showed why the Eagles are so keen to keep him amid speculation over his future as the Ivory Coast winger lashed home in the 85th minute.
For the first time in six years, United were beaten in their opening league game.
It was a chastening start to the season for United, who have come under fire from fans frustrated at their relatively modest transfer outlay compared to their title rivals.
- Free-scoring Leeds -
At Elland Road, promoted Leeds were involved in another eye-catching encounter in their first top-flight home match for 16 years.
After losing 4-3 at champions Liverpool on the opening weekend, Helda Costa fired Marcelo Bielsa's free-scoring side ahead in the fifth minute.
Fulham striker Aleksandar Mitrovic equalised from the penalty spot in the 35th minute after a foul on Joe Bryan.
Bryan was penalised himself for his shove on Patrick Bamford and Mateusz Klich restored Leeds' advantage with a 40th minute spot-kick.
In the 51st minute, Patrick Bamford steered a right-footed finish into the bottom corner.
Leeds struck again six minutes later with a superb strike from Costa.
Fulham pulled one back in the 62nd minute through Bobby Decordova-Reid and Mitrovic's towering header four minutes later set up a tense finale, but the promoted Cottagers fell to a second successive defeat.
Leeds' opening games have seen 14 goals, which is the most for a top-flight side's first two matches since Wolves in 1962-63.
At Goodison Park, Dominic Calvert-Lewin hit a hat-trick in Everton's 5-2 win over 10-man West Bromwich Albion.
Carlo Ancelotti's side fell behind to Grady Diangana's early goal.
But Calvert-Lewin equalised and James Rodriguez put Everton ahead with his first Premier League goal before Albion imploded.
Kieran Gibbs was dismissed for pushing James in the face in first half stoppage-time, a rash reaction that prompted him to issue a post-match apology taking "full responsibility" for his mistake.
Then Albion boss Slaven Bilic was sent to the stands after storming onto the pitch for a furious rant at referee Mike Dean.
Matheus Pereira equalised for Albion after the interval, but Michael Keane restored Everton's lead and Calvert-Lewin sealed the points with his second and third goals.
After a summer spending spree, Ancelotti is under pressure to deliver a big improvement on last season's 12th place finish and the early signs are promising.
Having beaten Tottenham in their opening game last weekend, Everton have started a Premier League season with consecutive victories for the first time since 2012-13.
"Of course today Dominic was the top scorer but also Richarlison did really well, the combination in front was good," Ancelotti said.
"They are supported by James, who is doing really well. I'm satisfied in front, we have to do better at the back."