Paul McKay, who featured for Gainsborough Trinity on loan this season, has left Doncaster Rovers for Leeds United.
The 19-year-old son of agent Willie McKay and his twin brother Jack have signed two-and-a-half year deals at Elland Road.
Both played in a Under 21 game for West Ham United last week and were linked with a move to the Hammers late last year.
Centre half Paul played the full 120 minutes of the Johnstone’s Paint Trophy clash with Burton Albion earlier this season - his only senior appearance for the club, before moving to Trinity on loan in November.
The youngster headed home the winner on his debut against FC United of Manchester.