David Moyes has hailed the role played by Lukasz Fabianski in West Ham's charge towards the Champions League.
Poland goalkeeper Fabianski last week signed a new contract to keep him at the London Stadium until next summer.
On Sunday the 35-year-old faces former club Arsenal, whose fans dubbed him 'Flappyhandski' following some shaky performances early in his career.
But Fabianski has put those unconvincing days firmly behind him to become the Hammers' undisputed number one.
West Ham boss Moyes said: "I have to say his recent form has been great and it's really helped us.
"There's not a club in the country that doesn't need a top goalkeeper, and we're lucky that we've got one.
"You've only got to look at Liverpool last year and how important the goalkeeper was, this year we're talking about Manchester City's keeper and how good he is.
"I think Lukasz is playing back to his best at the moment, his saves and the way he has been performing has been excellent. I'm glad we've got him for another year.
"How long can he go on? I don't know but I'm always going to try and bring in competition as much as I can. We need to think about that going forward, but he's been excellent."
Fabianski joined West Ham for a bargain £7million from Swansea in 2018, shortly after Manuel Pellegrini had replaced Moyes as manager following his first spell in charge.
Moyes revealed: "I remember when I was here last time I spoke to Paul Clement, who had just lost his job as Swansea manager. He said the goalkeeper is fantastic.
"I'd made my mind up that I was going to sign Lukasz and then we didn't get kept on, but the club got Lukasz anyway, so there's a little bit of history behind that.
"I think his performances and his consistency has been excellent, he's a great lad to work with and more importantly a very good goalkeeper.
"He's had a few ups and downs with injuries which has affected him but he's made some outstanding saves and helped us."
