Claudio Caniggia scored Rangers' third

But Rangers were rarely threatened after that and Claudio Caniggia added two more for a flattering scoreline but a deserved victory.

The pre-season First Division favourites have been mediocre in the league but had already accounted for SPL sides Kilmarnock, Hibernian, Dunfermline Athletic and Dundee in cup competitions this season.

Rangers boss Alex McLeish expected a tough encounter and made just one change from last week's Old Firm derby.

The experiment of using Neil McCann having failed, Russell Latapy took over that role with the Scot relegated to the bench.

Ayr boss Gordon Dalziel also made one change, Neil Duffy returning from injury to replace Craig McEwan in defence.

Hesitancy at the back from Ayr captain John Hughes almost handed Rangers the lead within the first five minutes.

But goalkeeper Craig Nelson pulled off an excellent, goal-line block from a Peter Lovenkrands volley off a Caniggia cross into the six-yard box.

A Hughes clearance had Tony Vidmar in trouble, but the Australian international defender made up for his mis-timed swipe by racing back to block with Brian McLaughlin clean through and poised to fire at goal.

McLaughlin had delayed his shot too long but almost made up for that after 29 minutes when he forced Rangers goalkeeper Stefan Klos into a stunning save.

The former Celtic winger's deft chip from 18-yards looked to be lifting over Klos until the German palmed the ball into the air and then grabbed it on the goal-line.

Russell Latapy (right) won a penalty

Latapy came close with a left-foot drive that edged past the far post then Klos had to turn a long-range, curling effort from Pat McGinlay over the top.

But it was Rangers who made the breakthrough after 43 minutes.

Caniggia turned past a couple of challenges before chipping through to Flo, who drove the ball low and in off the far post from 15 yards.

Ayr could count themselves unlucky to be behind, but they could have no complaints about the awarding of a penalty after 47 minutes.

Lovering was beaten by the pace of Latapy and hauled down the Trinidad and Tobago international.

Ferguson stepped up to send Nelson the wrong way from the spot.

That knocked the stuffing out of Ayr.

Caniggia added the third after 75 minutes, side-footing home a cross from substitute McCann, then added the fourth with his head in the dying seconds.