English Premiership club Newcastle on Monday announced the signing of Wales full-back Liam Williams on a one-year deal.
The 34-year-old, who has not played since suffering a knee injury in Wales's defeat by France in January, left Saracens at the end of last season.
"It's a good opportunity to experience something new, and I can't wait to get started," said Williams, who has won 93 caps for Wales.
"It's an exciting time to be joining Newcastle."
Energy drinks giant Red Bull completed its takeover of the club in August.
The Austria-based company has significant business interests in football, motor racing and winter sports.
Newcastle have finished bottom of the England's top rugby division in each of the past three seasons.
The club's director of rugby Steve Diamond said that Williams, who has also five test caps for the British and Irish Lions, would bring valuable know-how.
"Liam has done it all in terms of domestic, European and international rugby, but his enthusiasm for the sport remains as strong as ever," Diamond said.
"At this stage in our journey he gives us the kind of experience we need, and he's a proven winner."
Newcastle launch their league campaign on Friday at home to Saracens.
Guess who's back 👀
— Rugby on TNT Sports (@rugbyontnt) September 22, 2025
Liam Williams makes his return to PREM Rugby, joining Newcastle Red Bulls until the end of the season 🪽 pic.twitter.com/024OW15ozj