Michael van Gerwen began his bid for a fourth Paddy Power World Darts Championship title with victory over Keane Barry, while James Wade was the first seed to exit the tournament at the hands of Matt Campbell on Tuesday at London’s Alexandra Palace.
Three-time World Champion Van Gerwen was the headline act on Day Five, and he dropped just two legs in a dominant display over Barry, with the Irish youngster left to rue 14 missed doubles.
Van Gerwen averaged 98.17, pinning 60% of his checkout attempts, including a roof-raising 167 to progress to the third round.
"I'm happy to win my first game, and I'm happy with how I focussed today," said Van Gerwen.
"I'm pleased with my finishing but I could've done a lot more and I'm a little bit disappointed with my scoring.
"There's a lot of pressure on me and all the top players not to lose your first game; you don't want to let yourself down and you have to fight for every leg.
"I'm just happy to be coming back after Christmas and hopefully I can show what I can do."
Four-time World Championship semi-finalist Wade became the first seeded player to fall as he went down 3-2 to Canadian Campbell.
Wade twice led in sets at 1-0 and 2-1, but a resilient Campbell took the fourth set 3-0 to force a decider.
The final set began with an 86 checkout from Campbell before Wade missed three double attempts and the Canadian took full advantage to go 2-0 up.
Wade broke straight back with a 13-darter, but after he failed to take out 56 in the following leg, Campbell pinned double 18 at the first time of asking to wrap up the biggest win of his career.
"For sure, this is the biggest win of my career so far, because of where it happened," said Campbell.
"I'd never won on the Ally Pally stage in four attempts before this year so this tournament has been huge for me.
"I think winning my first game against Lourence [Ilagan] helped me win this game because it got the monkey off my back.
"Now I'm looking forward to enjoying Christmas and seeing how far I can go in this tournament."
Steve Beaton got his 23rd PDC World Championship off to a winning start as he secured a 3-1 win over Dutch youngster Wessel Nijman.
The evergreen Beaton produced a strong display, raising the roof with a 123 checkout on his way to winning the opening set, before winning the set two decider with a 14-darter to double his lead.
Debutant Nijman's response was immediate as he impressively reeled off three successive legs to win the third set and halve the deficit.
The second leg of set four saw both players leave a double after nine darts, and though Nijman won the leg to take a 2-0 lead, Beaton reeled off a trio of legs to book a second round meeting with Daryl Gurney.
"I think that was one of my best World Championship performances for a while," Beaton reflected.
"It was a really tough game, Wessel came out firing and I thought 'I'm in trouble here', but thankfully I found some good shots at the right times.
"I think playing a tough game first sets me up nicely for my next game.
"I still get the same buzz after all these years, playing in front of that crowd is unbelievable with the support I get."
Japan's Tomoya Goto enjoyed a dream Ally Pally debut as he dispatched of former World Championship quarter-finalist Ian White 3-1.
Goto, a winner of two PDC Asian Tour titles in 2023, took little time in settling onto the sport's biggest stage as he took the opening two sets.
White, who was also battling to keep his PDC Tour Card for 2024, rallied and took the third set, but was whitewashed by Goto in the fourth as the 27-year-old sealed his passage to round two where Ryan Searle awaits.
Jeffrey de Graaf picked up his first ever World Championship win, coming back from 2-0 down to defeat Ritchie Edhouse 3-2.
A keenly-contested encounter saw all of the first four sets go to last-leg deciders, as Edhouse missed a dart at tops to win 3-0.
De Graaf, representing Sweden for the first time in a World Championship, produced a magnificent fightback, winning another set decider in the fourth before finishing the stronger of the pair to seal his place in round two where he will take on Jose de Sousa.
Mike De Decker impressed in a 3-0 defeat of Dragutin Horvat as the Belgian progressed to the second round for a second consecutive year.
A strong display from De Decker saw him average 11 points more than his German counterpart as he breezed into round two, where he will meet Madars Razma.
Boris Krcmar also reached the second round stage for a second successive year with a 3-1 win over Keegan Brown.
Despite losing the opening set, Krcmar was the stronger player throughout and the Croat will now take on Dirk van Duijvenbode in round two.
German debutant Ricardo Pietreczko dropped just one leg in a 3-0 rout of Japan's Mikuru Suzuki, ending female hopes in this year's tournament.
The Paddy Power World Darts Championship continues on Wednesday, as two-time World Champion Peter Wright headlines a double session of first and second round action.
Former European Champion Ross Smith takes on Niels Zonneveld in the afternoon session, while Wright meets Welshman Jim Williams in the evening.
Click here for match stats & results.
2023/24 Paddy Power World Darts Championship
Tuesday December 19
Afternoon Session
3x First Round, 1x Second Round
Tomoya Goto 3-1 Ian White (3-2, 3-2, 1-3, 3-0) (R1)
Jeffrey de Graaf 3-2 Ritchie Edhouse (2-3, 2-3, 3-2, 3-2, 3-1) (R1)
Boris Krcmar 3-1 Keegan Brown (2-3, 3-0, 3-0, 3-2) (R1)
Matt Campbell 3-2 James Wade (1-3, 3-1, 1-3, 3-0, 3-1) (R2)
Evening Session
3x First Round, 1x Second Round
Steve Beaton 3-1 Wessel Nijman (3-1, 3-2, 0-3, 3-2) (R1)
Mike De Decker 3-0 Dragutin Horvat (3-1, 3-1, 3-2) (R1)
Ricardo Pietreczko 3-0 Mikuru Suzuki (3-0, 3-1, 3-0) (R1)
Michael van Gerwen 3-0 Keane Barry (3-1, 3-1, 3-0) (R2)
Wednesday December 20
Afternoon Session (1230 GMT)
3x First Round, 1x Second Round
Radek Szaganski v Marko Kantele (R1)
Steve Lennon v Owen Bates (R1)
William O'Connor v Bhav Patel (R1)
Ross Smith v Niels Zonneveld (R2)
Evening Session (1900 GMT)
3x First Round, 1x Second Round
Ryan Joyce v Alex Spellman (R1)
Richard Veenstra v Ben Robb (R1)
Christian Kist v Luke Littler (R1)
Peter Wright v Jim Williams (R2)