Scotland defender Ryan Porteous has joined Watford from Hibernian for a fee of about Â£450,000.
The 23-year-old was out of contract at Easter Road this summer and had turned down the offer of a new deal.
Porteous joined Hibs aged 13 and scored 13 times in 157 games after making his debut in the League Cup in 2017.
Hibs are looking at Bailey Wright and Stuart Findlay as replacements for Porteous and Rocky Bushiri, who will be out for three months through injury.
Australia central defender Wright, 30, played under Hibs manager Lee Johnson at Sunderland but has fallen out of favour at the Stadium Of Light.
Findlay joined Oxford United last summer after spending four years in the United States with Philadelphia and the 27-year-old former Kilmarnock centre-back – who has played once for Scotland – has been a regular in their team this season.
Porteous, who has signed a four-and-a-half-year deal with the Hornets, made his Scotland debut against Ukraine last September.
“‘Porto’ is a great example of how players from our excellent academy can progress into the first team and make a real difference,” said Johnson.
“He has a strong will to win, and we will miss him. I have no doubt he will go on and have a really successful career. We wish him all the best at Watford.”
Porteous will be managed by former Croatia centre-back Slaven Bilic at Watford, who were relegated from the Premier League last season.
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“Ryan has been a fantastic servant for the club and has been brilliant to deal with over the last few months,” added Hibs chief executive Ben Kensell.
“When it became clear he wanted to explore his options, we have worked hard to get the best deal for us, but also kept an eye on what is the best move for Ryan to propel his career.”
Hibs are sixth in the Scottish Premiership while Watford are third in the Championship and pushing for a return to the Premier League.
Find all the latest football transfers on our dedicated page.
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