Obertan turned out for Newcastle's under-21 side in front of 324 hardy souls at Whitley Park against Bolton Wanderers.
Donachie told nufcTV: "Coming down to play with lesser players is always difficult. It's easier the better players you're playing with.
"But I thought his attitude was very good - it was some of the players around him who didn't show the same consistency.
"He was outstanding for the goal and showed his class. It was difficult for Gaby and I was pleased with him."
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