The £300,000 tournament kicked off at the Ethias Arena in Hasselt on Friday, with the 32 players competing across two sessions in the first round of the three-day event.
Reigning champion van Gerwen found himself 2-0 down early on against youngster de Zwaan, who broke in the game's opening leg and then took out a superb 156 finish in a nerveless opening to his European Championship debut.
Van Gerwen, though, fired his challenge with a 13-darter as 180s in successive legs helped him to level, before finishes of 72 and 74 in the next three helped him take five in a row.
De Zwaan landed a 180 and double two to rally, but van Gerwen posted a maximum of his own and before posting tops to seal victory with another 13-dart leg.
"I was fairly happy with how I played, and especially how I came back after Jeffrey's good start," said van Gerwen. "He's a good player and he will do well in the game, but my aim is to defend my title and that's a good start."
Van Gerwen now faces Spain's Cristo Reyes, who impressed with a 100 average as he kicked off the European Championship with a 6-2 win over German teenager Max Hopp.
Hopp opened the game with a 180 as he took the first leg, but Reyes took out double 18, double eight and double 16 to move 3-1 up and added a 12-darter to regain that advantage before finishing 76 and a 14-darter to wrap up the win.
Belgian ace Kim Huybrechts gave the home crowd plenty to cheer with a 6-3 win over Mervyn King, as the Antwerp ace rounded off the first round in style.
Huybrechts - who lives in Antwerp and was being watched by his mother, partner and daughter - took out 108, double 18 and 83 on the bull as he stormed into a 3-0 lead.
King got off the mark in leg four on double 16 and then took out a superb 160 finish to pull back to 3-2, but he crucially missed the bull to level in the next, as double top edged Huybrechts away and a brilliant 11-darter gave him a 5-2 cushion.
King replied with a 14-dart finish, but Huybrechts landed a 180 and hit double eight in leg nine to complete the win, setting up a second round meeting with Peter Wright.
"I'm very proud," admitted Huybrechts. "I had so many of my friends and family here, and with it being the first big PDC event in Belgium it was extra special - but I've never had to deal with so much pressure before, so I'm happy to win.
"Being 3-0 up takes a lot of pressure away, but Mervyn came back and the 160 hurt a little bit and if he made it three-all he would have been the stronger man so going 4-2 up, so that made it a bit easier for me."
Huybrechts added: "I've played Peter a lot in the last two or three years and all the games have been exciting and close, and that's what I expect tomorrow.
"He usually has all the crowds on his side, so I'll be counting on the Belgian support and finally having them on my side!"
World number four Wright overcame European Championship debutant Alan Norris 6-3 as he won through to the last 16 in Hasselt earlier on Friday.
Norris held the early advantage at 1-0 and 2-1 before Wright took out 60 and 100 to edge ahead before producing a fine 11-darter to move 4-2 up.
Norris responded by taking out 130 for a 12-dart leg, but Wright wrapped up victory in style with 180s in back-to-back legs as another 11-darter secured his second round spot.
Four-time European Champion Phil Taylor punished Vincent van der Voort for missing 11 darts at doubles as he claimed a 6-1 win over the Dutchman, who had taken victory when they met in the World Grand Prix earlier this month.
Van der Voort actually led as he opened the game with a 14-darter, but six missed doubles in the second allowed Taylor to level and another miss in the third saw the 16-time World Champion move 2-1 up.
Taylor then opened the fourth leg with seven perfect darts, scoring 177 and 180, and though he was unable to complete a nine-dart finish, took the leg in 11 for a 3-1 lead.
Van der Voort then missed two more doubles as Taylor posted a third-dart double 16 to win the fifth leg, double 16 for a 14-darter to move 5-1 up before hitting a 180 and double five to complete victory.
Taylor now takes on Michael Smith, the former World Youth Champion who produced an impressive display of finishing as he took out six doubles from nine attempts in his 6-4 win over Gerwyn Price.
After Welshman Price took the opener, Smith finished 81 on the bull, 72 and 70 as he took a 3-1 cushion, only for the debutant to better those checkouts with a 161 finish before hitting double ten and an 11-darter to move 4-3 up.
Smith, though, hit a 180 as he levelled again with a 13-darter, before double ten moved him 5-4 up and a fine 14-darter wrapped up his win.
2013 European Champion Adrian Lewis edged a tight contest with Benito van de Pas as he overcame the Dutch youngster in a deciding leg to progress to a second round meeting with Justin Pipe.
Both players landed 180s in the opening leg as Lewis edged ahead, before the Dutchman levelled by taking out 101, and the next four were shared before Lewis hit tops and then broke throw on double five for a 5-3 lead.
Van de Pas broke back immediately on double ten, and when Lewis missed two match darts at double 16 the youngster posted tops to force a deciding leg.
Lewis, though, was first to a finish in the final leg, and though he initially wired double four with two further match darts, he returned to finally claim the win on double two.
Pipe landed four 180s and finished 50 percent of his darts at a double as he overcame Dutch debutant Dirk van Duijvenbode 6-2.
The Taunton ace made all the early running, finishing 82 in the opening leg and taking out legs of 13 and 12 darts - the latter with a 125 finish - to lead 3-0, before taking the next two to move to the brink of a whitewash win.
Van Duijvenbode took out a 14-darter to get off the mark and continued his revival on double ten, but Pipe ended the fightback in leg eight with a 108 checkout.
2012 European Champion Simon Whitlock began his bid to win back the title with a 6-2 defeat of Sweden's Magnus Caris, who led after taking the opening leg but never recovered from losing the next five as the Australian pulled clear.
Whitlock's run included two 12-dart legs, a 13-darter and a 104 checkout, and though Caris rallied briefly with a 180 as he took leg seven, the former champion took out tops in leg eight for victory.
Whitlock will now face reigning World Champion and Premier League champion Gary Anderson, who overcame a slow start to defeat Brendan Dolan 6-3.
Dolan finished tops for the opening leg and also shared the first four before Anderson hit top gear, edging 3-2 up with tops before breaking throw in leg six with the aid of two 180s.
He landed another maximum in taking a 5-2 lead, and though Dolan replied on double 15, another tops finish sealed Anderson's win.
Jelle Klaasen won his all-Dutch battle with Raymond van Barneveld 6-4 with another strong display as the two-time Players Championship winner in 2015 progressed to the last 16.
Klaasen defied an early 12-darter from van Barneveld with back-to-back 14-dart finishes as he moved 4-1 up, with the five-time World Champion hitting another 12-darter and a 64 checkout to pull back to 4-3.
Klaasen, though, fired in a 174 score and double 18 to win his fifth leg, with van Barneveld hitting back on double eight but unable to prevent his rival sealing victory with a 14-darter, which featured a 180 and double 18.
Klaasen now takes on James Wade, who knocked out 2014 European Championship finalist Terry Jenkins with a 6-3 victory.
Wade took the opening three legs to take command of the game, with Jenkins pulling back to 4-3 but crucially missing five darts to level in a key leg eight.
Left-hander Wade punished him by landing tops before firing in a 180 and double ten to seal victory on leg nine.
Dave Chisnall powered to six 180s against Mensur Suljovic - but still needed a 121 bullseye finish in the deciding leg of their clash to see off the in-form Austrian.
Suljovic, who has reached for ranking semi-finals during October, took out 98 and 118 to win the opening two legs before Chisnall, inspired by his first 180, edged a tight third - after four missed doubles from the Austrian - to get his challenge off the mark.
Chisnall landed another 180 in the fourth as he levelled and took the next two, as the pair traded maximums in both, for a 4-2 cushion, with three straight 14-dart legs and landed a fifth 180 in as many legs as he moved 5-2 up with a 12-darter.
Suljovic, though, hit back as a 171 score set up tops for a 13-darter, and a 14-dart finish was followed by a 111 checkout to punish Chisnall's miss at double 12 for the match, as the game went into a decider.
Chisnall landed his sixth maximum as the pair fought for victory, and when Suljovic missed the bull to finish 161 to snatch the win, the St Helens ace returned to hit the middle double to complete a 121 combination and claim a second round spot against Stephen Bunting.
Bunting also edged through an 11-leg thriller as he defeated Ian White 6-5 to reach the second round with the narrowest of wins, as the Stoke ace hit back from a three-leg deficit to send the contest all the way.
After landing tops to win the opening leg, Bunting finishes 60 and 66 for 14-dart finishes to move 3-0 up, only for White to take out double four, 75 and a 13-darter to level.
Bunting replied with a 13-darter and the next two were shared as the St Helens ace moved 5-4 up, with White landing another 13-dart finish to send the game into a deciding leg.
The former Lakeside Champion, though, hit his third 180 of the game at a key point before finishing 64 on double 18 to edge the win.
Big-finishing John Henderson knocked number five seed Robert Thornton out of the tournament by hitting three ton-plus checkouts in his 6-4 victory.
Scottish star Thornton had won the World Grand Prix three weeks ago and was aiming to follow up that Dublin triumph with further glory in the PDC's first major televised event in Belgium, at the Ethias Arena in Hasselt.
However, Henderson punished early missed doubles to take a 2-0 lead, hitting a 130 finish in the process, and also led 4-2 before Thornton took out 101 and 121 to level the match.
Henderson, though, hit back with a 121 checkout on double 11 before hitting two 180s and a thundering 111 finish to claim the win with a 12-darter.
Austria's Rowby-John Rodriguez held off a spirited comeback from Christian Kist to claim a 6-4 win from their first round game, despite the Dutch ace missing double 12 for a perfect nine-dart finish.
Rodriguez responded to losing the game's opening leg by taking the next five without reply, twice punishing missed doubles from Kist as he pulled clear.
Kist, though, finished 63 and double six to pull back to 5-3 before hitting two 180s to open the ninth leg, adding another treble 20 and treble 19 before pulling his dart at double 12 into the single nine.
He recovered to win the leg, but Rodriguez traded 180s with his rival in the tenth before hitting double ten to seal his second round spot against Henderson.
Saturday's second round is split across two sessions at the Ethias Arena in Hasselt as players compete for spots in Sunday's Finals Day, which features the quarter-finals in the afternoon and the semi-finals and final in the evening.
Tickets can be purchased through www.pdc-europe.tv.
Unibet European Championship
Friday October 30
Cristo Reyes 6-2 Max Hopp
Christian Kist 4-6 Rowby-John Rodriguez
Simon Whitlock 6-2 Magnus Caris
Justin Pipe 6-2 Dirk van Duijvenbode
Michael Smith 6-4 Gerwyn Price
Ian White 5-6 Stephen Bunting
Robert Thornton 4-6 John Henderson
Peter Wright 6-3 Alan Norris
Adrian Lewis 6-5 Benito van de Pas
Mensur Suljovic 5-6 Dave Chisnall
James Wade 6-3 Terry Jenkins
Gary Anderson 6-3 Brendan Dolan
Jelle Klaasen 6-4 Raymond van Barneveld
Phil Taylor 6-1 Vincent van der Voort
Michael van Gerwen 6-3 Jeffrey de Zwaan
Kim Huybrechts 6-3 Mervyn King
Saturday October 31
Afternoon Session (1.45pm-6pm local time, 12.45pm-5pm UK time)
John Henderson v Rowby-John Rodriguez
Stephen Bunting v Dave Chisnall
Adrian Lewis v Justin Pipe
Gary Anderson v Simon Whitlock
Evening Session (8pm-12am local time, 7pm-11pm UK time)
Peter Wright v Kim Huybrechts
Phil Taylor v Michael Smith
Michael van Gerwen v Cristo Reyes
James Wade v Jelle Klaasen
Second Round - Best of 19 legs