The Welsh youngsters lost 14-13 to Italy on Friday and WRU international skills coach Lewis says there is much work to do before they face Ireland on Tuesday.
Despite tries for Nathan Hudd and Jack Evans and a penalty for Arwel Robson, Wales were found to be lacking in many areas and are looking for an improved performance against Ireland on Tuesday.
“It was a very disappointing start to the tournament,” said the former Wales flanker.
“We knew Italy were a decent side as they’ve recently beaten France and pushed Ireland close, so we knew we had to play well, but our performance was nowhere near its best, there were too many mistakes and we lost the physical battle too.
“When you come up against a side who is highly motivated and well prepared, you are going to be in trouble if you are not 100% there mentally and a lot of lessons have been drawn from the match, for all of us.”
Ireland lost to Georgia on the opening day, so the sides play each other in the 5th place semi-final (Balma, 7pm).
“The one positive is that we have another two matches to try to put things right, and we have got stuck into training to start that process,” added Lewis.
Wales Under 18 FIRA-AER squad:
Backs:
Jack Evans (Scarlets/ Llandovery Coll/ Llandovery), George Gasson (Dragons / St Cenydd / Caerphilly), Keelan Giles (Ospreys/ Gower College/ Waunarlwydd), Shaun Pearce (Scarlets / Coleg Sir Gar/ Kidwelly); Owen Lane (Blues/ Cowbridge Comp), Connor Edwards (Dragons / Newport High School / Croesyceiliog), Kieran Williams (Ospreys / Neath Port Talbot Coll/ Glynneath), Rhun Williams (RGC / Llandrillo / Caernarfon); Arwel Robson (Dragons/ Lewis School / Penallta); Matthew Aubrey (Ospreys / Gower College / Pontarddulais), Efan Jones (RGC/ Rydal Penrhos / Wrexham)
Forwards:
Kieron Assirrati (Blues / Coleg y Cymoedd / Wattstown), Steff Thomas (Scarlets/ Coleg Sir Gar), Tom Mabley (Blues/ Cymoedd/ St Peters), Jordan Davies (Scarlets/ Carmarthen Athletic), Rhys Carré (Blues/ Cowbridge Comp/ St Josephs) , Ellis Shipp (Dragons / Coleg Gwent / Penallta), Jordan Liney (Ospreys/ Hartbury/ Dunvant), Max Williams (Dragons/Newport High School/ Caerleon), Callum Bradbury (Blues / Coleg Y Cymoedd / Beddau), Shane Lewis Hughes (Blues / Coleg Y Cymoedd / Ystrad Rhondda), Aled Ward (Blues / Cowbridge / Cardiff Quins), Mitchell Walsh (Ospreys / Gower College / Mumbles), Nathan Hudd (Drgaons/ Newport High School / Caerphilly), Joe Gaughan (Blues /Cowbridge Comprehensive / Glamorgan Wanderers), Josh Cole (Ospreys/Neath Port Talbot College / Tonmawr).
