Nicknamed "Superchin", he has won 5 ranking PDC titles, including the World Grand Prix in 2017 and the Players Championship Finals in 2018.

Gurney reached the quarter-finals of the 2008 Scottish Open, beating Andy Boulton and Alan Soutar before losing to Shaun Greatbatch.

[5] His best result in his debut year on the tour came at the German Darts Championship, where Gurney defeated Colin Lloyd, Ronnie Baxter and Simon Whitlock in reaching the quarter-finals, but his run came to an end when he lost 6–2 against Peter Wright.

[6] Gurney's second quarter-final appearance in the PDC was at a UK Open Qualifier in February 2014 which he reached by eliminating world number one Michael van Gerwen 6–5 with a 146 checkout.

He was beaten 6–4 by Andrew Gilding but the performance ensured he qualified for the UK Open itself for the first time and lost 5–4 to Ian White in the second round.

[7][8] Later in the year, Gurney made his debut in the World Grand Prix which he qualified for by being the second highest non-exempt Irish player on the Pro Tour Order of Merit.

[9] However, he bounced back later in the week when he won the Tom Kirby Memorial Irish Matchplay title by defeating Radek Szagański in the final.

[10] Gurney's Irish Matchplay title earned him a place in the preliminary round of the 2015 World Championship and Scott MacKenzie missed one dart to eliminate him 4–0.

[12] From the last 32 stage of the fifth UK Open Qualifier, Gurney beat Alan Norris, Peter Wright and Dave Chisnall to reach his first PDC semi-final where he was defeated 6–2 by Michael Smith.

[16] Gurney lost 2–0 in sets to Robert Thornton in the first round of the World Grand Prix, but two quarter-final exits saw him play in the Players Championship Finals for the first time.

He averaged 101.38 in a 6–2 victory over Kim Huybrechts and then knocked out reigning world champion Gary Anderson 10–4, winning the last six legs in a row, to reach his first major quarter-final.

[27] After breaking into the top 32 on the PDC Order of Merit in 2016, Gurney was a seeded player for the first time at the 2017 World Championship and beat Jermaine Wattimena 3–1 in the first round.

[28] Gurney missed five darts to win 4–2, but held on to take it 4–3 and become the first player from Northern Ireland to reach a PDC World Championship quarter-final.

[30] Comfortable victories over Alex Roy, Mark Webster and Vincent van der Voort saw Gurney advance to the quarter-finals of the UK Open.

Gurney followed the scare by defeating Brendan Dolan, before 10–2 and 11–3 wins over Chris Dobey and Danny Noppert to set up a final with Michael van Gerwen.

[44] Gurney won his first PDC European Tour title at the 2019 German Darts Championship, defeating Ricky Evans 8–6 in the final.

Gurney reached the final of the 2019 Melbourne Darts Masters, defeating Kyle Anderson, Simon Whitlock and Rob Cross along the way.

At the 2020 UK Open, Gurney reached the semi-finals, a run which included a 10–6 win over reigning world champion Peter Wright.

[52] Gurney reached the quarter-finals of the 2021 PDC World Darts Championship with wins over William O'Connor, Chris Dobey and Vincent van der Voort.

In June, Gurney reached the final of Players Championship 11, but missed out on winning the title in a last leg decider loss to Alan Soutar.

Gurney was among the Tour Card holder qualifiers for the 2024 World Series of Darts Finals, where he reached the quarter-finals after wins over Dirk van Duijvenbode and Gerwyn Price.

At the 2025 PDC World Darts Championship, Gurney recovered from 2–1 down to defeat Florian Hempel to set up a third round match against Jonny Clayton.