The Birkenhead-born 20-year-old got his first cap since choosing his allegiance with Republic of Ireland, and scored twice in a 2-0 win against Switzerland Under-21s. Both were second half headers, coming in the 61st and 74th minutes before being substituted to great applause late on.
Walters scored 5 goals for City in 11 starts while on loan from Bolton Wanderers last season. He has yet to play for the Trotters this term.