MICHAEL THOMAS has only scored twice at Anfield in his career. The first goal, three years ago, won the League championship for Arsenal. The second has given Liverpool the chance to win the FA Cup. After only four days in training, Thomas, who has missed the last nine games with a hamstring injury following his transfer in December, persuaded Graeme Souness to play him in the FA Cup quarter-final against Aston Villa. The gamble, together with Souness's decision to include Ronnie Whelan and John Barnes, paid off when they combined to provide Thomas with his chance in the 67th minute. The goal takes Liverpool to a semi-final meeting with giant-killers Portsmouth, probably at Villa Park on April 5, but, with the greatest of respect to Jim Smith's side, the Merseysiders appear to have a clear invitation to reach their fourth FA Cup final in the last six years. With the exception of a Saunders turn which left the otherwise immaculate McGrath on his backside, Liverpool had struggled to contain a vibrant Villa side. When Whelan cleared from defence in the 67th minute there was no apparent danger to the Villa rearguard until Barnes suddenly accelerated away from the tiring Richardson. He saw Thomas making a typically surging run from midfield and managed to thread the ball into his path as the midfielder changed gear and ran clear of substitute Kubicki. The finish was as assured as the goal that won the title for Arsenal on that memorable night in May 1989.