Rangers warmed up for Sunday's Ibrox Old Firm derby with a straightforward dismissal of bottom club St Johnstone.

Tore Andre Flo opened the scoring in first-half stoppage time and Fernando Ricksen doubled the lead on the hour mark.

The result pushed Saints ever closer to the mathematical reality of relegation and for Rangers it cut Celtic's lead at the top to 10 points.

A home win on Sunday will reduce it further but Celtic now have a game in hand in which to search for the four wins they need to retain the title.

Flo has not been a regular starter in recent weeks and the jury is still out on whether this was due to illness or whether Rangers boss Alex McLeish just doesn't fancy the £12million player he inherited from Dick Advocaat.

He started as though he intended to impress in time for Sunday however, forcing Ludovic Roy into a spectacular tip over in only the third minute.

The Norseman might have won his side a penalty in the seventh minute when he went down in the box under Jim Weir's challenge but referee David Somers made a snap decision to play on.

Rangers were to be denied by the crossbar twice before Flo put them in the lead, first when Roy tipped a Ricksen header on to the woodwork and then from a Neil McCann corner that found its way on to the head of the diminutive predator Billy Dodds at the back post.

Andrei Kanchelskis had also looked keen to get on the scoresheet, cutting inside from the right flank on one occasion only to fire straight at Roy, the St Mirren goalkeeper on loan until the end of a season that will surely see him relegated for the second successive season.

Kanchelskis supplied the cross for Flo's opener in first-half stoppage time and the striker's header was powerful and close enough to flash past the exposed goalkeeper.

Saints, who were without Keigan Parker and Sammy Youssouf, had offered little by way of attacking replies and had looked merely happy not to be losing until Flo struck, for the 24th time this season.

There was not much of an atmosphere as the home fans had little to shout about and the away contingent were no doubt saving their voices for Sunday.

The game had much a of a reserve match feel about it, which was not surprising given the Rangers line-up.

With Ronald de Boer, Barry Ferguson, Bert Konterman, Maurice Ross and Michael Mols all given extra time to recover from injuries in the hope of Sabbath returns, the likes of Dodds - who had a first-half strike ruled out for offside, Scott Wilson and Kanchelskis were given rare starts.

Ricksen was booked for a late challenge on Weir but made amends a couple of minutes later with the second goal.

Kanchelskis played Flo in behind a sluggish back line and Roy again was able to save his side with the faintest of touches, diverting Flo's attempt to loft the ball over him on to the far post.

But Ricksen was the first to the rebound and slammed the ball into the empty net.

Lorenzo Amoruso fired a free kick ludicrously wide even by his own erratic standards before Christian Nerlinger at last made his long-awaited comeback.

The German had been out injured since the first day of August but replaced Ricksen with 22 minutes remaining.

Flo had faded from the game by this point but popped up with a reminder why his is the most expensive enigma in Scottish football history.

The goal was at his mercy when Kanchelskis cut the ball back for him inside the six-yard box but somehow he managed to bounce the ball off the turf and over the bar.

It did not affect the result as, despite personnel changes, Saints could not find any of the punch up front that they had been so obviously lacking in the first half.

Teams

St Johnstone: Roy, Lynch, Dods, Weir, Lovenkrands, Maher, Dasovic, Kane (Macdonald 58), Murray, Jones (Falconer 77), Hartley.

Subs Not Used: Cuthbert, McCluskey, McBride.

Booked: Hartley, Dasovic.

Rangers: Klos, Wilson, Amoruso, Vidmar, Kanchelskis, Ricksen (Nerlinger 67), Hughes, Numan, Flo, Dodds, McCann.

Subs Not Used: McGregor, Caniggia, Latapy, Lovenkrands.

Booked: Ricksen.

Goals: Flo 45, Ricksen 61.

Att: 6,382

Ref: D Somers (Scotland).