It was a sensational display from Littler on finals Sunday in Wolverhampton, beating Gary Anderson 16-15 in an all-time classic semi-final before reeling in 15 legs in a row in a 16-3 domination of Martin Lukeman in the final.
The victory moves Littler up to fifth in the world on the PDC Order of Merit and the favorite for the World Darts Championship in just his debut year as a professional.
The first target for Littler is those rankings and he has his eye on being even higher than fifth in the world come the end of the year.
“I knew coming into the tournament, if I do get my hands on the trophy, which is a long way away, I’ll be up to No 5 in the world… No 5 in the space of 10 months.
“There’s still another two more ranking tournaments to go so hopefully I can go a bit higher than five.”
Since going on his mind-boggling run at the Worlds last December, Littler’s life has changed dramatically in every single aspect and he is now a recognised celebrity wherever he goes.
But for the 17-year-old, moments like the Grand Slam make it all worthwhile.
“I was just very happy with my performance,” he added.