Taty Castellanos scored his first goal for West Ham to end their 10-game winless run with a 2-1 victory after extra time over Championship side Queens Park Rangers in the FA Cup third round.
The striker Castellanos in a £25.2m deal from Lazio last week and scored in the first half of extra time to earn their first win since beating Burnley 3-2 in the Premier League on November 8.
Under-pressure West Ham boss Nuno Espirito Santo was smiling at full-time with relief, having had to wait 32 minutes for his side to have a shot as Crysencio Summerville forced Joe Walsh into an excellent save.
But Summerville wasn't to be denied in the first half after the hosts' centre-back Konstantinos Mavropanos was stretched off with a neck injury, which forced nine minutes of added time. Summerville scored in the tenth, smashing in from close range.
QPR, though, hit back midway through the second half when Richard Kone glanced Karamoko Dembele's cross beyond Mads Hermansen.
West Ham were the better side from then on, yet couldn't prevent the tie from going to extra time. They finally went ahead again when Summerville brilliantly turned away from Jimmy Dunne on the left before crossing for Castellanos to power home a header.
West Ham head coach Nuno Espirito Santo:
"It feels really nice [to win again]. It feels good for us, the fans, the boys. We started in control, dominant, but not creating much. Second half, we started really well. The combinations we achieved were something that needed to click.
"Overall, in terms of fighting, desire and character, I'm very pleased, especially in the situation that we're in. We conceded and bounced back. So important for us today.
"Goals bring confidence. Cry [Summerville] also had an assist and scored. Pablo came inside, Jarrod (Bowen) had an amazing game. Our front players did really well.
"Goals change everything, not only for them personally, but for us. It's going to change our week. We're going to feel better during the week, players are going to recover better.
"I think we can make a step and improve. Everything is going to be better this week."
On Mavropanos' injury: "It was a nasty one. His neck is very sore. He's in pain. We need to assess him for a couple of days, but hopefully he is going to be ok."
West Ham captain Jarrod Bowen told TNT Sports:
"Really important. When you're in our situation, all you need is a performance, a result to turn the season on its head. We knew coming into this game it wasn't going to be easy. A lot of pressure on us to perform and deliver, and it took 120 minutes.
"It speaks a lot about the squad that we stuck in there, kept going and going and going and got our rewards."
On Taty Castellanos: "He comes with a lot of experience, a really good player and person. He's played two games now and got his goal today so really happy.
"To get your first goal so quickly is really good for confidence. Really happy for him because we're going to need him to score more goals."
