Fellaini's first-half volley in the 32nd minute separated the teams at half-time and the game remained devoid of another score before a wave of goals in the last 11 minutes.
Midfielder Powell gave his team a 2-0 lead with a simple tap-in from a Fellaini pass with just over 10 minutes to go, but the Merseysiders were right back in the game as Jerome Sinclair and Madger Gomes scored quick-fire goals on the 83rd and 85th minutes.
The game was not over yet, as Sean Goss scored the winning goal for the home side from Fellaini's assist in the 89th minute.
First-teamer @Fellaini scored and set up the other two goals in #mufc Under-21s' exciting 3-2 win over Liverpool. pic.twitter.com/TAVFrSI0Td
— Manchester United (@ManUtd) November 30, 2015