The Japan international has been missing since October with a knee injury, while Danny Welbeck is given a chance to impress from the start against Steve Clarke's Baggies
The Japan international has been out for over two months with the problem sustained in a Champions League clash with Braga.
Sir Alex Ferguson had hinted on Friday that the playmaker could return to the bench for Saturday's clash, but he steps in from the start in place of Chicharito in attack.
Tom Cleverley and Ashley Young replace Paul Scholes and Ryan Giggs in midfield, while Robin van Persie is dropped to the bench and Danny Welbeck starts. Nemanja Vidic returns to the defence in place of Rio Ferdinand.
The Baggies hand a full Premier League debut to George Thorne as Steve Clarke makes seven changes to the side that beat QPR on Boxing Day.
Thorne replaces Youssouf Mulumbu in the centre, while Gabriel Tamas and Liam Ridgwell come in for Jonas Olsson and Goran Popov at the back.
It's all change in attack too with Markus Rosenberg, Graham Dorrans and Peter Odemwingie stepping in for James Morrison, Zoltan Gera and Marc-Antoine Fortune.
Shane Long spearheads the Baggies' frontline in place of Chelsea loanee Romelu Lukaku.
Manchester United starting XI: De Gea; Smalling, Vidic, Evans, Evra; Valencia, Carrick, Cleverley, Young; Kagawa; Welbeck
Subs: Van Persie, Ferdinand, Giggs, Buttner, Lindegaard, Hernandez, Scholes
West Brom starting XI: Foster; Jones, McAuley, Tamas, Ridgewell; Thorne, Brunt; Rosenberg, Dorrans, Odemwingie; Long
Subs: Myhill, Lukaku, Morrison, Jara Reyes, Fortune, Dawson, El Ghanassy