On manager Louis van Gaal’s 64th birthday the hosts rarely threatened the Tottenham goal as the Old Trafford crowd got their first glimpse of some of United’s close-season signings.
The visitors had chances of their own as they rallied late in the contest, but ultimately Walker’s own goal, in the 22nd minute, proved to be the difference.
Van Gaal, as he had promised in his pre-match press conference, did not select David de Gea, explaining that the Spain goalkeeper was not “capable” of the focus required for the match amid speculation linking him with a move to Real Madrid.
The Dutchman instead handed a debut in goal to Argentina international Sergio Romero, signed on a free transfer following his release from Sampdoria.
United also gave full debuts to forward Memphis Depay, midfielder Morgan Schneiderlin and right-back Matteo Darmian.
With four new faces, United’s play was fragmented and passes went astray as they struggled for rhythm during a first half in which none of their players managed a shot on target.
Tottenham almost took the lead in the sixth minute when Harry Kane scooped a clever ball over the top of the United defence for Christian Eriksen, who lifted his effort over the crossbar.
Despite their uncertain start United took the lead, albeit fortuitously, with an own goal from Spurs right-back Walker after Juan Mata had intercepted a lazy pass from Nabil Bentaleb.
