Martin O'Neill knows Celtic will not have the support of many neutrals on Saturday, admitting "everyone" wants Hearts to win the Scottish Premiership title.

Celtic and Hearts will face off in a blockbuster clash on the final day of the Scottish Premiership season, with the title at stake. 

Following Wednesday's highly contentious 3-2 win at Motherwell, Celtic know a victory in front of their own supporters will clinch their 56th league title and a fifth in a row.  

That would make them the Scottish Premiership's most successful club outright, surpassing the 55 titles won by rivals Rangers. 

Meanwhile, if Hearts avoid defeat, they will win their fifth top-flight crown – the most of any non-Old Firm club and their first since 1959-60.

They would be the first club other than Celtic and Rangers to be crowned champions of Scotland since Alex Ferguson's Aberdeen in 1984-85, ending a run of 40 consecutive titles won by the two Glasgow giants.

The build-up to Saturday's match has been dominated by fierce debate over the last-minute penalty that handed Celtic victory over Motherwell – a draw would have meant Hearts could have won the title even with a two-goal defeat at Celtic Park.

Following a VAR review, Motherwell's Sam Nicholson was controversially penalised for handball after jumping to challenge Auston Trusty, with Hearts manager Derek McInnes describing the decision as "disgusting".

When asked about the debate surrounding the incident, O'Neill said: "It's obviously been magnified because of the occasion as much as anything else.

"Am I surprised? No, I'm not surprised, because everybody wants Hearts to win. It's really as simple as that.

"Everybody outside Celtic and the Celtic diaspora wants Hearts to win. And so if it wasn't Hearts, it would be Rangers, it would be somebody else. That's the nature of it."

O'Neill admitted that football's lawmakers should review what constitutes handball during the off-season, but he firmly believes that, by the letter of the law, it was a penalty.

"One, I think it's a penalty. I think he's handled the ball. When you see it again properly, it is a penalty," O'Neill insisted. 

"In the wider scheme of things, I think that we, everybody should be looking at this. Throughout Europe, we have seen penalties given where we all think, 'well, that wouldn't have happened years ago'.

"It looks very, very harsh. This should be a major point of discussion in the summer, to have a look again, to see what they're doing. 

"It should be absolutely straightforward. In this accidental handball, hands in unnatural positions and stuff like this, people are maybe even being pushed into situations – I think all of that's got to be looked at.

"But, as the rules stand at this minute, that was a penalty."