Earlier today, Leitrim feather Dearbhla Rooney had been edged out on a 3-2 split by Thai fighter Panpatchara Somnuek and it was the same result this evening for Clancy versus Panamerican silver medallist Stevens.
The European Youth and Junior silver medallist, still an under-18s fighter next year, was left aghast at the verdict.
It was a cagey opener, with the much-smaller Stevens looking to speedily counter Clancy who looked unable to find a rhythmn against the awkward American southpaw.
Clancy was better able to impose his physicality in the second and was starting to catch the Hawaiian as he came in.
The Yeats County man went on the front foot in the final round but Stevens countered well until a strong finish for Clancy.
Going to the cards, both boxers were convinced they had won but, much to Clancy’s disbelief, Stevens was awarded the bout and will now go on to face French fighter Ibrahim Boukedim, a European Youth bronze medallist, in the Last 16 on Thursday evening.
It was a second 3-2 defeat of the day for Ireland, with a 30-27 and a 29-28 not being enough for Clancy whose opponent was handed three 29-28 cards.
Ireland have two boxers in action tomorrow in Budapest.
European Junior and Youth gold medallist Daina Moorehouse fights Spaniard Marta Lopez, who she defeated in April, in the light flyweight Last 16 while European Schoolboys silver medallist Brandon McCarthy boxes Indian Akash Kumar in the bantamweight Round of 32.
Tuesday August 21st
57kg Dearbhla Rooney (Ireland) lost to Panpatchara Somnuek (Thailand)
52kg Dean Clancy (Ireland) v Asa Stevens (USA)
Wednesday August 22nd
56kg Brandon McCarthy (Ireland) v Akash Kumar (India)
48kg Daina Moorehouse (Ireland) v Marta Lopez (Spain)
Thursday August 23rd
51kg Caitlin Fryers (Ireland) v Kittiya Nampa (Thailand)
49kg Jude Gallagher (Ireland) v Renuex Zhao (China)
Sunday August 26th
75kg: Lauren Kelly (Ireland) v Tallya Brillaux (France) (afternoon)
48kg Daina Moorhouse (Enniskerry)
49kg Jude Gallagher (Two Castles)
51kg Caitlin Fryers (Immaculata)
52kg Dean Clancy (Ballinacarrow)
56kg Brandon McCarthy (St Michael’s Athy)
57kg Dearbhla Rooney (Sean McDermott)
75kg Lauren Kelly (St Brigid’s Edenderry)
Team manager: Stephen Connolly and Tara Mari Robins
Head coach: Billy McClean
Coaches: Michael Carruth, Michael Mongan, Anita Just
Physio: David Cooke