West Ham have re-signed goalkeeper Darren Randolph from Middlesbrough on a three-and-a-half-year deal.
He previously spent two years with the Hammers before departing for Boro in the summer of 2017.
After confirming his move back to the London Stadium, Randolph said: "I'm delighted to be back at West Ham.
- LISTEN to the latest Sky Sports EFL Podcast
- Download here to listen to it later!
- Subscribe via iTunes | Castbox | Spotify
"I had two great years at the club previously and still have a lot of friends here, so I had no hesitation in coming back.
"West Ham is a massive club, with fantastic supporters and an excellent squad of players. It's a great challenge for me and I am really looking forward to working with the goalkeepers here and helping the team in any way I can.
"This opportunity was simply too good to turn down. It's a great feeling to be back in the Premier League with such a fantastic club and I can't wait to get started."
Randolph made 42 appearances for West Ham during his first spell at the club, and has 39 caps for the Republic of Ireland.
His return gives West Ham extra cover for Lukasz Fabianski, who is expected to be out for the next few weeks after being forced off during last week's defeat to Sheffield United with a hip injury.
The Poland international previously missed three months of the season after having surgery on another hip problem.
That meant West Ham were forced to rely on No 2 Roberto, who was dropped after several poor performances, and No 3 David Martin, who had never previously played in the Premier League.
Boro make move for Stojanovic
Middlesbrough have acted quickly to replace Randolph and are in advanced negotiations with Swiss club St Gallen for Dejan Stojanovic.
The fee for the Macedonia U21 international will be around £1m.