Robert Snodgrass is set to become Sam Allardyce's first signing at West Brom after the club agreed a deal with West Ham.
An 18-month deal for the 33-year-old Scottish winger has now been agreed, pending medical and final paperwork.
"I think as long as the medical goes alright, by tomorrow Robert Snodgrass will be a West Bromwich Albion player, which I'm delighted with," Allardyce said.
"I'm delighted that he's chosen to take up the challenge with us and trying to bring us a bit more Premier League experience and quality into the squad."
Sky Sports News understands there was other Premier League interest in Snodgrass, but he will join Allardyce's relegation-threatened side.
Snodgrass' West Ham contract was due to run out in the summer and he is deemed surplus to requirements by David Moyes at the London Stadium.
A permanent move for the former Scotland international leaves Allardyce's remaining loan slot available for another signing, after Chelsea midfielder Conor Gallagher joined the Baggies on a season-long loan in September.
Snodgrass, who joined West Ham from Hull City in January 2017, has scored two goals in six appearances for the Hammers this season.
West Brom sit 19th in the Premier League with eight points from their opening 17 games of the season and are without a win from Allardyce's opening four games since he replaced Slaven Bilic in December.
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