GLASGOW (Agencies) - Motherwell captain Stephen Craigan scored his first goal for five years on Saturday to help his team beat St. Johnstone 3-0 and reach the Scottish Cup final for the first time since it last won the trophy in 1991. The 34-year-old central defender headed in from a fifth-minute corner that eluded goalkeeper Enckelmans attempted catch, Murphy scored with a low shot from the edge of the area in the 14th and John Sutton made it 3-0. with a 25-meter (yard) shot six minutes before halftime. Twenty years after beating Dundee United 4-3 in the final, Motherwell will meet Celtic or Aberdeen on May 21 at Hampden Park. With Celtic playing Aberdeen in the second semi-final match at Hampden Park on Sunday, Rangers beat St. Mirren 2-1 to leapfrog its great rival and go one point clear at the top of the Scottish Premier League. Sasa Papac and Steven Whittaker scored at Ibrox for the defending champions, while Hearts drew 1-1 at Inverness in Saturdays other league match.