The forward scored with both feet and with a header, while Kenny McEvoy also hit the target as the lads responded well to a disappointing first day in Ploufragan on Friday, in which we lost out twice on penalties.
Coach Ugo Ehiogu confirmed he was pleased with the reaction he saw from the players in the 4-1 win and praised Harrison for his endeavours in attack.
“It was a much improved performance today and the individuals applied themselves very well,” he said. “We worked very hard, showed our quality and our ruthlessness saw us win the game comfortably.
“It was pleasing to see Shayon come out with three goals as well – I was impressed with him and his willingness to close down and press. He’s had the perfect hat-trick – left foot, right foot and header – so that was just reward for his application.”
Goalkeeper Alfie Whiteman made an important stop in the opening stages of the 50-minute game before Harrison gave us a 24th-minute lead.
Within 60 seconds it was 2-0 as Nathan Oduwa was hauled back in the box with Harrison converting the resulting penalty.
And two minutes after half-time the forward took advantage of some confusion among the Guingamp defence to complete his treble.
McEvoy was denied by the goalkeeper on 44 minutes as a good chance went begging, before Guingamp pulled a goal back through Zaniou Sana five minutes later.
McEvoy had the last laugh, however, blasting home in the final minute to complete the scoring.
We now meet FC Lorient in Sunday’s third place play-off, kick-off 1.45pm (12.45pm UK time).
Spurs U21s (vs EA Guingamp): Whiteman, Walkes, Walker-Peters, Veljkovic (Amos 40), Carter-Vickers, Hall, Sonupe, Azzaoui (McEvoy 37), Harrison (Sterling 37), Goddard, Oduwa.