The 16-year-old is highly-rated by the Hornets, who have already offered a three-year deal on top of a scholarship, but he will train at Carrington before weighing up his options
Watford starlet Ogo Obi has joined Manchester United on trial, Goal can confirm.
The 16-year-old is rated as one of the best players for his age in the country, and Watford have been desperate for him to agree professional terms at Vicarage Road.
The Hornets rate Obi so highly they have offered him scholarship terms with a three-year deal attached.
Obi, though, is yet to decide where his long-term future lies and has readily accepted the chance to link up with United, after Watford agreed to let him train with the Red Devils.
Chelsea, Arsenal and Liverpool have also expressed an interest in Obi, but United are in pole position.
Under the Elite Player Performance Plan, Watford would be due compensation should the player opt to join United or any other club.
Louis van Gaal's side are also said to have taken highly-rated Portuguese duo Joao Filipe and Joao Virginia on trial from Benfica.
Both players are 15, Virginia is a goalkeeper and Filipe a forward who has been likened in some quarters to Cristiano Ronaldo.