Divine Mukasa scored twice as West Ham beat Wolves 4-2 to pick up their first three points since last season's relegation to the Championship.
Wolves, who also went down from the Premier League last term, could have gone top with a victory but ended up losing for the first time under new manager Cesar Peixoto.
Jarrod Bowen and Konstantinos Mavropanos also scored for the hosts, with Marshall Munetsi and Mavropanos' own goal replying for Wolves.
The win eased the pressure on manager Nuno Espirito Santo on a night when Amanda Staveley, who is heading a consortium looking to buy a significant stake in West Ham, was at the London Stadium.
West Ham struggled initially and were relieved when Raul Jimenez, picked out in space in the box by Jackson Tchatchoua, shanked wildly wide.
Jimenez's next attempt, from a corner played almost to the edge of the box, was better though. The Mexico striker's shot bounced off the turf, over goalkeeper Mads Hermansen and on to the top of the crossbar.
Mateus Mane also hit the bar not long afterwards, from the left of the box after Kyle Walker-Peters had failed to cut out a cross. The full-back recovered to get just enough of a deflection on the shot that followed.
A goal was coming and it was the hosts who scored it against the run of play in the 33rd minute.
Mukasa, the on-loan Manchester City midfielder, unleashed a rising drive from more than 20 yards that went in off the underside of the crossbar.
West Ham were a team transformed, with Munetsi having to block on the line from Max Kilman.
And they were awarded a penalty in the 40th minute for Andre's lunge on Joel Piroe. Bowen sent goalkeeper Jose Sa the wrong way to slot home.
Wolves hit back in the 43rd minute when Munetsi won a chase with Mavropanos that saw him turn the Greek defender and end a low drive beyond Hermansen's dive to his left.
West Ham increased their lead in the 53rd minute through Mukasa. The teenager accepted Bowen's pass from the right and saw his shot loop off the boot of Nasser Djiga to leave Sa helpless again.
Sa batted away a Bowen drive from an angle but West Ham made it 4-1 in the 64th minute through Mavropanos' goal from the resulting corner. The centre-back saw his header deflected on to the crossbar but lashed home the rebound, also off the bar.
Wolves pulled a goal back in the 69th minute when Mavropanos, sliding in to stop Tchatchoua setting up substitute Jordan James, diverted the ball into his own net.
West Ham's Nuno Espirito Santo:
"We all know it was much-needed, this win. The way we are trying to grow and to improve, there were mistakes again today that we need to correct but we were able to be dominant.
"The attacking actions today were much more effective and this is the direction we hope for the team.
"If we look at the goals we conceded requires more than anything focus, concentration and determination. We must get there, there are a lot things to work on."
On Mukasa's performance: "I'm delighted, not only for the goals but the way he played, the positions he took in the middle of the park. He is a young player with a lot of things to improve but I'm delighted to have him.
"I value a lot the goal as you can imagine but more than anything was his position, the way he distributed the ball, the way he supported and defended. And if he can score then fantastic."
Wolves' Cesar Peixoto:
"It was not the result we wanted, we created a lot of chances to score. But congratulations to West Ham, they scored more goals.
"Their first goal was a great goal, a shot like that is impossible to defend, but for five minutes after that we were quite disorganised and conceded the penalty. West Ham's third goal was a little lucky.
"For the corners and the free-kicks my goalkeeper was blocked all the time and for the fourth goal they score. It is an unfair result. Two goals difference is unfair.
"The last game we won 4-1 and nothing was 100 per cent good. In this game nothing was 100 per cent bad. When we went 4-1 down the team reacted to score one more.
"The good thing is that the team stayed organised and as a team to the end. It was an amazing effort from the players but we have to improve some things."
