The former Players Championship Finals winner saw off his higher-ranked opponent with an impressive 99 average in the first round of the famous double-start tournament on Monday.
And Australian World Cup star Nicholson admitted that the match could hardly have gone better for him, as he set up a last 16 clash with world number one Phil Taylor.
“I’m very happy with that,” said Nicholson, who recovered from losing the first set to seal a 2-1 success. “It was a very focused performance and a lot of thought went into the game, so to say that I’m happy is an understatement.
“Robert’s a very good friend of mine and I was very relaxed, and I treated the game as just a darts match. It was a fantastic game and I stuck to the task because I knew how tough it was going to be, and I had a plan that worked for me.
“I played really well in the first set but the comeback shows the character I’m trying to build. I was under pressure and it’s a hard format because the best of three sets is tough, but to beat Robert is a great privilege.”
Nicholson later took to twitter to pay tribute to Thornton, saying: “What more can I say about @TheThorn180. A gentleman in defeat, but a friend who has helped me immensley. Robert brings out the best in me as a professional.”
Nicholson will face ten-time champion Grand Prix champion Taylor on Wednesday evening, with a place in the quarter-finals up for grabs.
By Chris Murphy