Micky Mellon admits the rewards are "huge" as Dundee United seek to boost their top-six hopes by ending the 100 per cent home record of runaway Scottish Premiership leaders Rangers.

With just four games to play before the split, United are behind sixth-placed St Mirren only on goal difference following successive wins over Ross County and Livingston.

Champions elect Rangers, 15 points clear of Old Firm rivals Celtic, are bidding for a 15th consecutive league success at Ibrox this season and have conceded just once on home soil.

The Terrors were thrashed 4-0 in their last Glasgow meeting with Steven Gerrard's men but manager Mellon wants his players to adopt a fearless approach on Sunday.

He said: "We know the size of the task, but why not go and give it a good go? Why not go and believe?

"We will go down there full of optimism and believe that we can answer the questions right. And go and be excited about that.

"What an opportunity, look at the size of the prize – the size of the prize is huge, worth fighting for, so let's go and have a go.

"We all know about the size of Rangers as a football club and the team that they've put together.

"But we've just got to go down there and try and be the best versions of ourselves.

"There will be many questions asked of us and we know that we've got to get all or most of them right in order to go down there and get a result."

Dundee United were promoted as Championship champions at the end of the curtailed 2019-20 season.

Mellon is satisfied with the progress made since but is eager for further improvement and challenged his players to "seal the deal" of securing a top-half finish.

"We never get carried away. It's been a tough old season," he said.

"You have got to go and seal the deal now, that's what good players do.

"Good players, good clubs, good teams will go and seal the deal and get into the top six and now the challenge for us is, are we good enough to go and seal the deal?

"Up until now, to come out of the Championship and be in the situation we're in – although we believe we should have been better in good parts of games and good parts of the season – that's decent going for us.

"But it doesn't mean to say we've not got ambition to improve or want to get better.

"We know there's still a lot, lot of hard work to be done."