St Johnstone could draw a degree of confidence from their victory over Rangers seven days ago. But the Cup statistics pointed to another probable outcome because, in ties stretching back to 1902, the Perth club had failed to win in 11 attempts.
Not surprisingly, St Johnstone started with the same side and gameplan as they did at McDiarmid Park last week but Rangers made an interesting switch, pulling Rod Wallace back into midfield and restoring Stephane Guivarc'h, the side's under-performing striker. With Colin Hendry back after injury, there was no chance that the manager was likely to call at least one defender "a poser" this time.
Coaches either earn their money or lose their jobs by making these kind of judgment calls. Dick Advocaat could afford to preen himself at Celtic Park after only 13 minutes when his tinkering brought Rangers the kind of goal he had so obviously planned. Its origins lay in Albertz's pass to Van Bronckhorst, but it was the Dutchman's incisive pass which set McCann free on the left.
He held up his cross long enough for Wallace to make the unmarked late run and his strong low shot was too wide of his body for goalkeeper Main to stop.
The Rangers goal left St Johnstone in a quandry. They had clearly laid out the team to soak up pressure and midfielders Dasovic and Kane were anchored just in front of the central defenders, unwilling to move forward. To make matters worse McBride limped off injured in the 22nd minute to be replaced by the tiny Portuguese Simao.
They seemed to be waiting for the roof to fall in and the hand of Advocaat could be seen in the 33rd minute when Rangers scored a second goal that came straight from the training pitch and one of the endless setpiece routines that only occasionally buy a reward.
Albertz and Van Bronckhorst lingered for a long time over a free kick, seemingly unsure of what to do next.
The midfielder eventually wandered away as if to join the waiting pack at the far post. When he was halfway there, the German rolled the ball to the Dutchman and he hit a strong shot deflected off Bollan beyond Main and into the net.
Rangers kept up the pressure at the beginning of the second half and Van Bronckhorst saw a shot go narrowly wide of the target.
Advocaat made a change in the 56th minute, bringing off ineffective Guivarc'h and bringing on Jonatan Johansson.
St Johnstone were finding it difficult to cope with the wave of Rangers attacks and Main took a 30-yard shot from Albertz at the second attempt.
Rangers were in full control and Johansson almost added a third in the 61st minute when he was released by Albertz, only for Main to block his shot.
Then the keeper got in the way of an audacious chip from McCann before Rangers added a third goal in the 62nd minute.
Main made a hash of corner from Albertz and Johansson was lurking at the far post to score.
Rangers made it 4-0 in the 70th minute when Albertz picked out McCann and he drove the ball beyond the stranded Main.
Van Bronckhorst, who put in a superb performance, said: "We are right on course - we are in the final and six points clear in the League and we have got our spirit back today.
"We lost our concentration last week but today we concentrated from the start and it was a good team effort.
"My free-kick was one we had practised. Everyone expected Jorg Albertz to shoot but he touched it to me and I shot and, with a slight deflection, it went in.
"We did well today, especially in the first half - we showed we wanted to win the game and were aggressive."
ST JOHNSTONE: Main, Dasovic (Griffin 73), Weir, Kernaghan, Grant (Lowndes 65), Kane, Bollan, O'Halloran, McBride (Simao 22), McAnespie, Dods. Booked: Kernaghan.
RANGERS: Klos, Porrini, Amoruso, Kanchelskis (McInnes 71), Van Bronckhorst, Albertz, Guivarc'h (Johansson 56), Wallace, McCann, Vidmar, Hendry (Wilson 76). Booked: Vidmar. Goals: Wallace 15, Van Bronckhorst 33, Johansson 62, McCann 70.
Referee: J McCluskey (Stewarton).
