Erling Haaland marked his Premier League debut with two statement strikes as champions Manchester City brushed West Ham aside with ease.
The 60million Euro summer signing, 22, missed an open goal in last week's Community Shield loss to Liverpool.
But he showed exactly why Pep Guardiola had been so keen to sign him with an assured finish in each half at a subdued London Stadium.
His first came in the 36th minute from a penalty he had won himself, bursting on to Ilkay Gundogan's pass and tricking substitute goalkeeper Alphonse Areola into bringing him down.
The ex-Borussia Dortmund man made it 2-0 in the 65th minute with another example of how he can power beyond defences.
Kevin De Bruyne's precision pass sent him sprinting into the box for another left-footed finish.
West Ham, who had delayed City's title surge by holding them to a 2-2 draw in May, looked nothing like the potent counter-attacking side of that day. David Moyes' hosts managed just two shots on target, including a header from new signing Gianluca Scamacca.
Fabianski 6 (Areola 28, 5); Coufal 6, Zouma 7, Johnson 7, Cresswell 6; Soucek 6, Rice 7; Bowen 6 (Downes 90, 3), Lanzini 5 (Benrahma 57, 5), Fornals 6 (Coventry 90, 3); Antonio 5 (Scamacca 57, 6).
Randolph, Vlasic, Oko-Flex, Ashby.
Ederson 6; Walker 7, Dias 7, Ake 7, Cancelo 8; Gundogan 7 (Silva 78, 5), Rodri 7 (Phillips 88, 4), De Bruyne 8 (Palmer 88, 3); Foden 7 (Mahrez 88, 4), Haaland 8 (Alvarez 78, 5), Grealish 6.
Ortega, Stones, Lewis, Wilson-Esbrand.
Michael Oliver 6