Yan had the first shot of the game when he was afforded space to shoot from 20 yards. But it was a tame effort, easily fielded by Anders Lindegaard.
Sir Alex handed summer signing Nick Powell his first start in a United shirt but it was a debut that got off to a bad start when he was caught by a nasty studs-up challenge by Shouting Wang.
Thankfully the 18-year-old was able to continue, although there was more disappointment for Powell on 23 minutes when he dragged the ball wide after he'd sprung the offside trap and latched onto a clever lofted pass by Davide Petrucci.
It was the only clear-cut chance United fashioned in a first half that almost ended disastrously when Lindegaard was forced into a fine save to deny Griffiths just before the break.
It's perhaps unrealistic to expect too much from a squad cobbled together from those first-team and Reserves players not resting from major tournaments, competing in the Olympics or currently injured. And pre-season, remember, is predominantly about gaining match fitness.
Nevertheless, Sir Alex will have been disappointed by the lack of entertainment and cutting-edge play in the final third. Only Petrucci and Kagawa provided any occasional sparks in the opening 45 minutes.