Gianluca Skamakka scored his first goal for West Ham on Thursday, beating Danish minnows Viborg 3-1 in the European Conference League play-offs.
West Ham, who reached the semi-finals of the Europa League last season, are coming into the match after back-to-back defeats to Manchester City and Nottingham Forest in the Premier League.
But Italy international Schamacca, who signed for £30m from Sassuolo, found a target in the 23rd minute to ease the tension after another new signing, Maxwell Cornetto, took the ball away.
Jarrod Bowen added a second in the 64th minute, and five minutes later Vibault scored one back for Jakob Bonde.
Substitute Michael Antonio scored West Ham’s third goal with 12 minutes remaining to secure the Londoners through to the group stage.
“Gianluca is probably very pleased and I am just as pleased,” said West Ham assistant boss Billy McKinley, standing in for suspended manager David Moyes.
“Strikers are judged by their goals, so being able to score quickly is a big thing and he has so much more.”
2021 Europa League champions Villarreal overcame an early shock by beating Hajduk Split 4-2.
Stipe Biuk gave Hajduk a second-minute lead, but the Spanish side quickly recovered to lead 4–1 by the break.
José Luis Morales doubled, Marco Ribaja’s own goal and Gerardo Moreno’s goal in stoppage time gave Villarreal the lead.
But Marco Fosati’s penalty five minutes before the start gave Hajduk hope to overturn the deficit in next week’s second leg.
The 32-time Belgian champions Anderlecht separated from Swiss Young Boys with a 1-0 victory thanks to a goal from Hannes Delcroix just before the hour mark.
Former Arsenal star Mesut Ozil was left on the bench as Turkey’s Basaksehir lost 1-1 to Antwerp in Istanbul.
Cologne, who finished third in the Bundesliga after two games, lost 2-1 at home to Hungarian Fehervar.
Florian Dietz took the lead in the 15th minute, but five minutes later Julien Chabot received a red card to reduce the number to 10.
Fehervar pounced on Budu Djivzivadze and Parco Dardai to take the lead before the break.
In the Europa League, Hearts gave up a 1-0 lead and lost 2-1 to Zurich, but start next week as favorites in their first European game in six years.
Scotland won a Lawrence Shankland penalty after fouling Australia international Nathaniel Atkinson.
However, the Swiss champion scored a goal within two minutes.
After Adrian Guerrero equalized with a 32nd-minute volley, Blelim Zemail added a second after leaving unmarked.
Hearts coach Robbie Neilson told BBC Scotland: “I thought it was great tonight.
“Last season we came to the Swiss champions who had a great season with international players.”
Hungary’s Ferencvaros became the biggest winners in the Europa League as Adama Traoré scored twice in a 4-0 loss to Ireland’s Shamrock Rovers.
Former Bournemouth and Watford striker Josh King scored an eighth-minute goal for Fenerbahçe in a 2–0 victory over Austrian Wien.