League Two side Stevenage have received an undisclosed club-record fee from Watford for defender Ben Wilmot.
The England Under-19 centre-back, 18, has signed a five-year contract with the Premier League club, having only made his professional debut in October.
Wilmot played 15 times in all this season but sat out Stevenage's last six games as negotiations advanced.
"Watford are getting an outstanding young man and footballer," said Stevenage chairman Phil Wallace.
"A record sale is huge news for the club and financially, extremely useful. We will ensure the funds are used sensibly and in the best interests of Stevenage FC."
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