Chris Kane scored a hat-trick on his return to the St Johnstone starting line-up as the Perth side eased past Albion Rovers 4-0.
Saints were comfortable winners at Cliftonhill as they set up a trip to Hearts in the William Hill Scottish Cup fifth round on February 10.
Kane opened the scoring inside three minutes of the rearranged tie and also set up Kyle McClean's first goal for the club.
The striker carried on where he left off after netting four goals in his final six matches on loan with Queen of the South.
The pitch passed a 2pm inspection after two earlier postponements, but St Johnstone wasted no time in taking control of the tie.
Kane volleyed home from eight yards after Joe Shaughnessy's long throw was allowed to bounce.
The striker had a header saved from the same source and Saints were relatively comfortable for the rest of the half, although the lively Connor Shields and Ross Davidson forced saves from long range.
The same pair were cautioned for reckless challenges before Shaughnessy joined them in the book for a foul from behind, but Saints took the sting out of the game in the early stages of the second half.
Kane won the ball on the right six minutes after the break and checked inside before delivering a cross which the untracked McClean stabbed home from six yards.
The 23-year-old forward headed home from close range six minutes later following Liam Craig's excellent cross.
He completed his treble with 20 minutes left when he raced on to a ball over the top and volleyed home from 18 yards.