Subsitute striker Eccleston fired off target from a difficult angle and Suso shrugged off Ezekiel Fryers but curled wide after skipping past Ritchie De Laet.
Although Petrucci's free-kick drifted dangerously past the far post ahead of Michael Keane and Tom Thorpe, Joyce's side struggled to carve out too many openings and there was a real scare when Eccleston spurned a golden headed opportunity from a cross by Ngoo with only three minutes remaining. However, Eccleston got it right in the 91st minute by tucking a neat finish past Johnstone after Emmanuel Mendy latched onto a Suso pass and stretched to send over an inviting pull-back.
De Laet's header from a Luke Giverin corner deflected just wide, amid more appeals for handball, as United showed resilience to try and regain the lead in the dying seconds but instead had to settle for a point.
United: Johnstone; Vermijl (Giverin 88), M.Keane, De Laet, Fryers; Cole (Fornasier 65), Thorpe, Tunnicliffe, Petrucci, Lingard (Blackett 92); W.Keane. Subs not used: Jacob, Ekangamene.