Duncan Ferguson admitted he replaced Everton substitute Moise Kean just 18 minutes after throwing him into the action at Manchester United because the 19-year-old "struggled" to adjust to the pace of the game.
Kean, a £27.5 million summer signing from Juventus, had been introduced as a 70th minute replacement for Brazilian winger Bernard during the 1-1 draw at Old Trafford.
But after an unimpressive contribution, Kean was replaced by Oumar Niasse 18 minutes later before walking straight down the touchline and into the dressing room.
"I was looking for a guy who could handle it better," Ferguson said.