The 19-year-old, making his top flight bow for the Magpies, powered a low shot from 22 yards beyond David de Gea to score what proved to be the only goal of the game.
He also won man of the match and his effort had already been chosen as Match of the Day's goal of the month, while Longstaff received his first call up for England's under-20s on Friday.
And now the North Shields-born youngster, who was presented with a commemorative ball from the Premier League earlier this month to mark his debut, as well as recognising the development and support given by his club, Academy, friends and family along the way, has another award to add to his growing collection.
Speaking after receiving his trophy, Longstaff said: "If I thought back to pre-season, I don't think I'd be picking up the award but for it to happen is pretty good.
"I think the biggest thing was just trying to get a good connection on it and hoping that it went towards the goal, and thankfully for me it ended up hitting the back of the net.
"From hitting it, I still can't remember much - I just remember running away to the fans.
"It's been a bit of a whirlwind, I think everything comes at you pretty quick, even getting recognised around the street happens a lot more, but I guess it's what you want and it's been good so far."
Also nominated were Brighton & Hove Albion's Aaron Connolly, for the second of two goals he scored against Tottenham Hotspur; Aston Villa's Douglas Luiz, for a strike against Norwich City; Gylfi Sigurdsson of Everton, for an effort against West Ham United; Leicester's James Maddison, who scored in the Foxes' 9-0 win against Southampton; Burnley man Jay Rodriguez, for his goal against Chelsea; and Man United's Anthony Martial for a strike against Norwich.