Michail Antonio's late goal earned West Ham a 1-0 victory over 10-man Bournemouth in their first Premier League match at the London Stadium.
For most of the afternoon, it looked as though the Hammers were set to be frustrated on their league debut at their new home, with clear chances scarce at either end.
However, after Harry Arter was shown a second yellow card for bringing down Cheikhou Kouyate, the hosts got the breakthrough as Antonio headed home from Gokhan Tore's cross in the 85th minute.
Adrian pulled off a sharp save to deny Josh King in injury-time and Jonathan Calleri spurned a brilliant chance for a goal on his Premier League debut when he shot wide with just the keeper to beat.
Before Arter's dismissal there had been little to excite a club-record attendance of 56,977, as the action on the pitch failed to match the occasion.
The Hammers were not helped by the unavailability of a number of first-team players, including striker Andy Carroll, who is facing a few weeks out with a knee injury.
Dimitri Payet and Sofiane Feghouli were also not involved, along with club-record signing Andre Ayew, who has been ruled out for several months after suffering a thigh injury in the opening game against Chelsea.
Bournemouth made one change from last weekend as Ryan Fraser replaced Lewis Cook.
In their only previous competitive match at the London Stadium, in the Europa League, the Hammers scored twice in the first half, but a repeat of that looked unlikely throughout a tight opening 45 minutes.
While the hosts dominated possession, they struggled to create any clear chances.
Gokhan Tore shot over the bar and then might have won a penalty when he was fouled right on the edge of the box by Charlie Daniels, with a free-kick given instead.
It took until the 40th minute for the first shot on target as Artur Boruc kept out a near-post shot from Enner Valencia.
The visitors rarely threatened in the opening 45 minutes, but went close after the interval as Josh King's long-range shot was brilliantly tipped over by Adrian.
At the other end, Tore volleyed into the side netting, but opportunities remained at a premium until Arter was dismissed in the 78th minute for bringing down Kouyate.
The Hammers then pressed for a winner and it was Antonio who delivered, heading home at the back post from Tore's cross.
King almost equalised in injury-time when he saw a close-range shot kept out by Adrian, before Calleri raced clear, only to shoot wide.
Player ratings
West Ham: Adrian (7), Byram (6), Collins (6), Reid (7), Masuaku (6), Nordtveit (6), Tore (6), Noble (6), Kouyate (7), Antonio (7), Valencia (6).
Subs: Obiang (n/a), Fletcher (n/a), Calleri (5).
Bournemouth: Boruc (6), Francis (6), Cook (6), A.Smith (6), Daniels (6), Surman (6), Arter (5), Fraser (6), Ibe (5), King (6), Wilson (6).
Subs used: Ake (n/a), Gosling (n/a), Grabban (6).
Man of the Match: Michail Antonio