Mark Kitching's back-post tap-in gave Boro the advantage after only eight minutes, with Joe Wheatley striking home from the edge of the box shortly after the break to double the visitors' lead.
Will Miller pulled one back for us just prior to the hour mark but we were unable to find an equaliser.
Spurs U21s: McGee, J Pritchard (Goddard 77), Stylianides (Edwards 58), Lesniak (c), Maghoma, Walkes, Sonupe, Winks, Harrison, Onomah, Miller. Substitutes (not used): Oduwa, McDermott (GK).
Middlesbrough U21s: Fryer, Johnson, Burn (c), Morris, McGinley, Tinkler, Cooke, Wheatley, Jakupovic, McAloon, Kitching. Substitutes (not used): Maloney, Tavernier, Curry, Jowers, Pears (GK).
Below: Joe Pritchard takes on Mark Kitching