Inverness manager Terry Butcher admits neighbours Ross County's Scottish Cup success against Celtic last season is a source of inspiration as they prepare to face Neil Lennon's men in the quarter-finals.
County shocked Celtic 2-0 in the semi-finals last season after beating Hibernian in the previous round, before coming up short against Dundee United in the final.
"You have only got to look across the water towards Dingwall and Ross County's fantastic run last season," Butcher said. "It certainly helped them financially and from a football point of view, it lifted them right up."
Inverness have already proved they can compete with the Old Firm this season and they are looking for their third Scottish Cup victory over Celtic when the teams meet in a rearranged contest at the Tulloch Caledonian Stadium.
Butcher said: "We want to replicate that and go one better but we have to beat Celtic."
Inverness came from behind to draw at Celtic Park in December after losing 1-0 to the Hoops on their return to the Clydesdale Bank Premier League in August.
Rangers needed three attempts to beat Caley Thistle this season, and then only did so by one goal. But it is the one heavy loss Inverness have suffered against the Glasgow teams that is driving Butcher on.
The Inverness manager picked a young and under-strength team to play Celtic at Parkhead in the Co-operative Insurance Cup in September, when Inverness were still finding their feet back in the Clydesdale Bank Premier League.
"We ran Celtic close here in the opening game of the season," Butcher said. "We have drawn against Rangers at Ibrox and drawn against Rangers here. The only blip was the 6-0 defeat in the League Cup against Celtic but we had a different team out that day.
"The priority was the St Mirren game on the Saturday in the SPL, which we won. So that was mission accomplished that week, even though we went out the cup. So we now have a chance for revenge and a chance to make progress."