In the quarter-finals, he lost to world number 3 at the time, James Wade but his tournament performance lifted him into the top 50 on the PDC Order of Merit.

After his performance in the World Championship, Nicholson decided to leave the DPA and play in the PDC Pro Tour in an attempt to qualify for the UK Open.

Nicholson reached the semi-final of the PDPA Players Championship Barnsley 2, defeating Gary Mawson, Mark Dudbridge, John MaGowan, Justin Pipe and Denis Ovens before losing out to Colin Osborne, the eventual winner.

During the latter stages of the tournament, the crowd started to support Nicholson due to his efforts against higher ranked and more experienced opponents (in particular Taylor), and as a result he relaxed his behaviour leading many pundits such as Alan Warriner-Little to suggest that he might give up the 'bad boy' image and just be himself.

At the 2011 World Matchplay, Nicholson defeated Colin Osborne in the first round to secure a second-round match with Raymond van Barneveld.

Together they had victories over Ireland, Belgium and the Netherlands to reach their first World Cup final, where they played the English pair of Phil Taylor and Adrian Lewis.

Australia found themselves 0–3 down in the final, meaning that Nicholson had to beat Lewis in the last singles match and then win the doubles to force the tie to a sudden-death leg for the World Cup crown.

Australia won both of the matches 7–4 and in the sudden-death leg Whitlock and Nicholson both missed two darts each to secure the title, with Lewis hitting the winning double for England.

He faced compatriot Whitlock in a first all Australian final on the PDC ProTour and lost 1–6, admitting afterwards that he had run out of steam by the conclusion of the tournament.

[10] After all 33 ProTour events of 2012 had been played, Nicholson was 18th on the Order of Merit, inside the top 32 who qualified for the Players Championship Finals.

[13] In his third World Cup of Darts with Simon Whitlock the pair were beaten in the last 16 when the Belgian brothers of Ronny and Kim Huybrechts defeated them 1–5.

[14] On 16 & 17 March 2013, Nicholson had wins over Dave Chisnall, Ross Smith, Darren Whittingham, Louis Blundell, Kim Huybrechts, Brendan Dolan, Co Stompé, Richie Burnett and Ronnie Baxter to secure back-to-back quarter final spots in the Speedy Services UK Open Qualifier 3 & Qualifier 4 events in Wigan.

He then claimed wins over Dean Winstanley and Mark Webster to secure a semi-final clash with world number three Michael van Gerwen.

[20] In the opening round of the World Matchplay he saw 4–1 and 8–7 leads over Dave Chisnall turn into a 10–8 defeat and was in tears on the stage during the final leg.

[25] Nicholson and Whitlock won through to the semi-finals of the World Cup of Darts where they faced England's Phil Taylor and Adrian Lewis in a repeat of 2012's final.

Whitlock was beaten 4–1 by Taylor, before Nicholson overcame Lewis 4–2 to mean a doubles match was required to settle the tie which Australia lost 4–0.

[26] Nicholson overcame Robert Thornton 10–8 in the first round of the World Matchplay, explaining later that his form had suffered over the previous months due to pains in his neck and shoulders which he has worked with an acupuncturist to help relieve.

[29] Nicholson walked onto the stage without sunglasses for the first time in his career at the 2015 World Championship in a further attempt to move away from his bad boy of darts image.

His first round match against Benito van de Pas went to a deciding set in which Nicholson lost all three legs to exit the tournament.

[31] He returned to play the full schedule of events and qualified for the third round of the 2015 UK Open in which he drew Michael van Gerwen and lost 9–3.

[42] The rest of Nicholson's year was good enough to give him enough ranking money to qualify for the 2017 Players Championship Finals, although being the 59th seed meant he had to play Michael van Gerwen and lost 6–3.

During his walk-on in his second-round match against Raymond van Barneveld in the 2011 World Matchplay, Nicholson mimicked WWE wrestler CM Punk by having X's marked on his hands, and also lifted up a Nexus scarf.

Then, when he met Phil Taylor, he once again mimicked CM Punk during his walk-on, using his signature pose on one knee, shouting "It's clobberin' time" and punching the air.