The tournament, formerly known as the Chemistry Cup, sees 21 of the world’s top boxing nations converge on Cologne.
Nine Irish boxers were in Day 1 Last 16 actions, four posting wins but five being eliminated.
A strong start saw Kurt Walker and Carly McNaul score victories before five straight defeats – with Joe ard and Emmet Brennan book-ending the day with victories.
Antrim talents Walker and McNaul recorded wins versus Armenian feather Eric Petrosyan and Polish flyweight Angelika Krysztoforska in the opening session.
The wheels then threatened to come off as Rio Olympian Brendan Irvine, Wayne Kelly, Kieran Molloy, James McGivern, and Dean Gardiner all bowed out.
Kelly and Gardiner produced top-class performances against Cuba’s Jorge Moiran and Russia’s Sergei Egorov but lost by the narrowest of margins – 3-2 split verdicts.
Irvine, in his first international fight back since injuring his hand last May, dropped a unanimous decision to Brit Galal Yafai while his fellow Belfast man McGivern was also beaten 5-0 by Dutch Olympian Enrico Lacruz.
There was no joy either for welterweight Kieran Molloy who was defeated by Mongolian Otgonbaatar Bymba
There was a good end to the day, however, as Brennan and Ward, who is aiming for his third gold medal at this level, claimed two wins on the trot over Polish pair Rafael Perczynski and Piotr Sczukowski
Ward, Brennan, McNaul and Walker will be back in action tomorrow along with the returning Christina Desmond, Grainne Walsh – who rematches German Nadine Apetz who she controversially lost to in the 2017 EUs, Tony Brown and medal machine Michaela Walsh.
Chemistry Cup (World Cup) Cologne, Germany
56kg Kurt Walker (Ireland) beat Eric Petrosyan (Armenia) 5-0
51kg Carly McNaul (Ireland) beat Angelika Krysztoforska (Poland) 5-0
63kg Wayne Kelly (Ireland) lost to Jorge Moiran (Cuba) 2-3
63kg James McGivern (Ireland) lost to Enrico La Cruz (Netherlands) 0-5
69kg Kieran Molloy (Ireland) lost to Otgonbaatar Bymba (Mongolia) 0-4
91kg+ Dean Gardiner (Ireland) lost to Sergei Egorov (Russia) 2-3
52kg Brendan Irvine (Ireland) lost to Galai Yafai (England) 0-5
75kg Emmet Brennan (Ireland) beat Rafael Perczynski (Poland) 5-0
81kg Joe Ward (Ireland) beat Piotr Sczukowski (Poland) 5-0
51kg Carly McNaul (Ireland) v Enkh Enkhjargal (Mongolia
57kg Michaela Walsh (Ireland) v Delgerkhnga Khongorzul (Mongolia)
57kg Kurt Walker (Ireland) v Albert Batyrgaziev (Russia)
69kg Christina Desmond (Ireland) v Liu Yang (China)
69kg Grainne Walsh (Ireland) v Nadine Apetz (Germany)
75kg Emmet Brennan (Ireland) v Gleb Bakshi (Russia)
81kg Joe Ward (Ireland) v Jilei Zhang (China)
91kg Tony Browne (Ireland) v Zhiabao Wang (China)
51kg Carly McNaul (Holy Family)
57kg Michaela Walsh (Monkstown)
69kg Christina Desmond (Fr Horgan’s)
69kg Grainne Walsh (Spartacus)
52kg Brendan Irvine (St Paul’s)
57kg Kurt Walker (Canal)
63kg James McGivern (St George’s)
63kg Wayne Kelly (Portlaoise)
69kg Kieran Molloy (Oughterard)
75kg Emmet Brennan (Glasnevin)
81kg Joe Ward (Spartacus)
91kg Tony Browne (St Michael’s)
91kg+ Dean Gardiner (Clonmel)
Team Manager: Bernard Dunne
Coaches: Zuar Antia, John Conlan, Damian Kennedy
Physiotherapist: Muireann Harte
Physiologist: Damain Martin