West Ham avoided a false start at the London Stadium with a 3-0 Europa League qualifying win over Slovenian minnows NK Domzale on Thursday.
Cheikhou Kouyate scored twice and new signing Sofiane Feghouli opened his account as the Hammers, who left Upton Park at the end of last season, secured a 4-2 aggregate win to reach the final playoff round before the group stage.
The venue formerly known as the Olympic Stadium welcomed its new tenants and West Ham could scarcely have wished for more obliging opposition as they overturned last week's shock 2-1 first-leg loss in Ljubljana.
It did not take long for the players to settle into their new surroundings, with Kouyate grabbing his slice of history with the first goal after just eight minutes. Enner Valencia cut the ball back to Sam Byram, who made a mess of his shot but the ball bobbled as far as Kouyate for a simple back-heel from six yards out.
Kouyate grabbed the second, and edged West Ham ahead in the tie, in the 25th minute when Andy Carroll nodded down Michail Antonio's cross into his path for a neat, low finish.
With nine minutes remaining, Feghouli raced onto Mark Noble's pass and crashed in the killer third to prolong West Ham's European adventure.
Bundesliga side Hertha Berlin also exited at an early stage after a Teemu Pukki hat trick carried Brondby to a 3-0 win at home.
Pukki erased Hertha's slim 1-0 lead from the first-leg inside three minutes, and though Vedad Ibisevic put the German club back in front on the half-hour mark, Pukki hit his second goal four minutes later.
Hertha still were in position to advance on away goals when Per Skjelbred hit a poor back pass and the former Celtic man pounced to complete his hat trick in the 52nd minute.
Meanwhile, Scotland's Aberdeen crashed out of the Europa League with a 1-0 loss to Maribor as a bizarre own goal killed off their hopes with a 2-1 aggregate defeat in Slovenia.
Adam Rooney missed a penalty midway through the first half and substitute Jayden Stockley was sent off for two bookings before Graeme Shinnie's attempted back pass bounced over the foot of goalkeeper Joe Lewis and into his own net.
Lille are also out following a 1-0 defeat to Qabala in Azerbaijan, the Ligue 1 side exiting 2-1 on aggregate.
Following a first-leg draw, Filip Ozobic put the hosts in front with a rocket from 25 yards that held up.
There was better luck for fellow French side Saint-Etienne, who got a 23rd-minute goal from Robert Beric to win at AEK Athens and go through 1-0 on aggregate.
Sassuolo had a much easier time, as Domenico Berardi scored twice, the second from the penalty spot after Ricardo Costa was sent off, and the Italian club beat Lucerne 3-0 to advance with a 4-1 aggregate scoreline.
Irish side Cork City missed out on the playoffs when they fell 2-1 to Genk in their home leg and lost 3-1 on aggregate.
For the rest of the results from Thursday's second legs of the Europa League third qualifying round, see the scoreboard page.