Norwegian defender Brede Hangeland made himself a Craven Cottage hero as Fulham held on for a superb 1-0 victory over Arsenal to atone for their opening weekend defeat at Hull.
Arsenal's performance exposed some clear flaws in Arsene Wenger's team just four days before their Champions League second-leg qualifier against FC Twente.
This was their first defeat of the season and a worrying one which ended with captain William Gallas remonstrating with referee Martin Atkinson and an assistant referee.
But the visitors deserved all they got after a poor display in the opening 45 minutes.
Arsenal had a first half to forget, while Fulham led from the 21st minute, shortly after Robin van Persie missed a sitter when new boy Samir Nasri's mis-kick from Theo Walcott's cross left the Dutchman a gaping goal to aim at from eight yards.
Fulham went straight up the other end, forced a corner and centre-back Hangeland charged in on Jimmy Bullard's low flag kick while Gallas and Kolo Toure stood and stared. He slotted home without any fuss for his first goal for Fulham.
Arsenal struggled to beat West Brom in the Barclays Premier League last week and a single goal decided the result then at the Emirates Stadium.
This time Gallas and Toure seemed like strangers in defence, and although Emmanuel Adebayor's header from Bacary Sagna's cross hit the right post soon after Fulham's opener it was an isolated incident of danger.
Fulham could have had at least two more goals before the break.
Arsenal tried to impose their possession game in the early stages but were caught out when Zoltan Gera slipped a fine ball through to Bobby Zamora in the inside left channel in the eighth minute.
Zamora glided in behind the defenders but carelessly chipped a poor shot over the crossbar from a difficult angle when he should have waited for support to arrive.
Arsenal were then grateful to Gael Clichy for getting back to dispossess Zamora shortly afterwards when the former West Ham striker came raiding again, this time down the Fulham right.
Arsenal's first shot finally came after 12 minutes when Van Persie's pass found Adebayor and the Togo international neatly controlled the ball but fired a low drive off target from 20 yards.
Danny Murphy drove a volley over the bar when Gunners, briefly down to 10 men with Emmanuel Eboue limping off, could only half-clear Gera's cross.
Arsenal had hardly sparkled but should have gone ahead in the 18th minute through van Persie, who was promoted from substitute last week.
And they paid a heavy penalty when Fulham grabbed the lead the opportunist effort by 6ft 5ins Hangeland.
Fulham's luck held when Adebayor's header from a Sagna cross came back off a post but, still without injured #10.5 million signing Andrew Johnson, were good value for their advantage at the interval.
A few sharp words from Arsene Wenger at the interval no doubt brought Arsenal's massive improvement in the second period, but although the pressure on Fulham grew by the minute, there were few chances created.
Van Persie shot wide with a crisp effort trying to make amends for his first-half blunder and new boy Nasri ran his socks off.
But the replacement of a nearly anonymous Theo Walcott by the muscular Nicklas Bendtner made little difference and there was just no penetration to go with Arsenal's possession.
Football Results
West Brom 1-2 Everton Everton recovered from a dismal opening 45 minutes to register their first win of the campaign
Tottenham 1-2 Sunderland Sunderland striker Djibril Cisse came off the bench to score the winner at White Hart Lane on his debut
Stoke 3-2 Aston Villa Mamady Sidibe netted in injury time as Stoke claimed a dramatic 3-2 victory over Aston Villa
Liverpool 2-1 Middlesbrough Liverpool captain Steven Gerrard fired a stunning stoppage-time winner to floor Middlesbrough 2-1
Blackburn 1-1 Hull Blackburn and Hull maintained their unbeaten starts to the Premier League campaign after a 1-1 draw at Ewood Park
Newcastle 1-0 Bolton Owen sent a timely reminder of his goalscoring prowess to Newcastle owner Ashley to kill off Bolton's stubborn resistance
Man Utd 1-1 Newcastle Manchester United's desperate need for a striker was laid bare as the champions began their title defence with a 1-1 draw with Newcastle
Aston Villa 4-2 Man City Gabriel Agbonlahor bounced back from his England snub with an eight minute hat-trick as Aston Villa poured more misery on Mark Hughes' side
Chelsea 4-0 Portsmouth Luiz Felipe Scolari got his Chelsea reign up and running with a 4-0 victory over Portsmouth at Stamford Bridge
West Ham 2-1 Wigan What looked like an opening-day stroll for West Ham turned into a real battle for a 2-1 win as gutsy Wigan fought back at Upton Park