BRUCE RIOCH'S FA Cup odyssey, which began with Bolton coming perilously close to ignominy at the hands of non-League Gretna in the first round, moved into overdrive yesterday with the taking of a third major Premiership scalp. Rioch's skilful team, who had followed a surprise third-round replay victory at Everton with an even more startling success at the home of holders Arsenal, were well deserving of their latest triumph at the expense of a sadly off colour Aston Villa. Alan Stubbs, whose late equaliser at Goodison Park had created the chance of an extra-time passage, was their hero again yesterday, finding time to spare from an another commanding display in the heart of defence to drive home a splendid free-kick eight minutes from the end. Stubbs' decisive strike made Villa, who had been humbled by another First Division club, Tranmere, in the semi-finals of the Coca- Cola Cup last Wednesday, regret a negative approach which suggested a replay was their principal objective. A Villa goal here rarely looked on, Dalian Atkinson and his second-half replacement, Dwight Yorke. making a mess of their two best chances, and their only other threats coming from Dean Saunders' near-post flick and Andy Townsend's sharp shot, both of which whistled just wide. Bolton, by comparison, frequently looked dangerous even though clearcut opportunities were at a premium. They almost broke through in the first half when full-back Jimmy Phillips rattled the underside of Mark Bosnich's crossbar after playing a one-two with Owen Coyle. They were just as close to taking the lead early in the second half when a Tony Kelly free-kick from 25 yards got Bosnich in a tangle. The Australian goalkeeper could only push the ball into the air and was relieved to see Andy Townsend hack it clear. There was no joy in the Villa camp. "We must get our heads up again and get something out of the season" said Paul McGrath. "We're bitterly disappointed but Bolton are a busy side."