Goalkeeper Mat Ryan has joined Arsenal on loan until the end of the season.
The 28-year-old Australian international joined Albion in June 2017 shortly after the club were promoted to the Premier League.
He was the club's first choice for almost three and a half seasons, before being overtaken by Rob Sanchez in mid-December.
Head coach Graham Potter explained, “Mat has been a great servant to the club in the Premier League, and he has played no small part for the club at this level.
“We have incredible talent and competition at this club for just one position, and understandably, as Australia's number one, Mat wants the chance of more regular opportunities.
“Mat is a pleasure to work with, a consummate professional and someone who works incredibly hard at his game. We wish him well at Arsenal and will be watching his progress there.”
Ryan has made 121 Premier League appearances for Albion, keeping 28 clean sheets along the way.
One of his standout moments was his late penalty save at Stoke City in February 2018, which secured a vital point during Albion's first season in the Premier League.
He joined Albion for a then club-record fee from Valencia on a five-year deal in 2017, having spent the previous season on loan at Genk.