Ryan Porteous is Watford's fourth signing of the January transfer window
Watford have signed defender Ryan Porteous for what Hibernian say is a "significant six-figure" fee.
The 23-year-old Scotland international, who made 157 appearances for Hibs, has agreed a four-and-a-half-year deal.
His final game was last weekend's Scottish Cup home tie against Edinburgh rivals Hearts, who won 3-0.
"He's a ball-playing centre-half, he steps in, he has an element of confidence about him," boss Slaven Bilic told BBC Three Counties Radio.
"He's a young player with experience and it's a refreshment of the squad, a cosmetic change - we lost [William Troost] Ekong, who has played the most minutes of all the centre-backs since I've been here, and he [Porteous] is homegrown and a leader."
Porteous is Watford's fourth signing this month following fellow defender Joao Perreira, midfielder Matheus Martins and striker Henrique Araujo.
He made his international debut in Scotland's Nations League game with 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 Hibs manager Lee Johnson.
"He has a strong will to win, and we will miss him. I have no doubt that he will go on and have a really successful career."
Watford are third in the Championship, but 13 points adrift of the top two before Saturday's trip to Middlesbrough, as they seek an immediate return to the Premier League.
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