Has last-gasp Celtic penalty undermined Hearts' hopes?

"We go there confident and we've been top of the league all season. It's a 90-minute cup final. If you offered us that at the start of the season we would have taken it."

A fourth match without defeat against their nearest rivals would seal one of the most unlikely triumphs ever in Scottish football, and former Hearts midfielder Michael Stewart is confident they can get the job done.

"There's no reason why Hearts can't win the title," he said on Sportscene.

"As much as there's disappointment, scepticism and a lot of ill-will coming off the back of [Wednesday], Hearts need to focus on the positives.

"They are capable of getting the result they need to win the trophy."

Will Parkhead atmosphere prove difference?

It will not be straightforward, though, and the pensive faces on the pitch and in the stands at Tynecastle on Wednesday reflected that.

While they are unbeaten at home in the league - with 15 wins and four draws - Hearts have been less sure on the road, losing five and drawing four of 18.

Celtic Park is a daunting place to go, but Hearts - as mentioned - have already won there this season, as have Rangers and Hibernian.

Still, former Celtic captain Scott Brown believes the capacity home crowd will be a huge factor.

"It's going to be so nervy," he said. "I think 60,000 fans at Celtic Park will make a difference. It would have been different if was a draw [at Fir Park] and Celtic had to score three or four goals.

"But at home, to win a title in front of your own fans on the last day of the season, that's how the [Celtic] players and manager would want to do it."

Brown's former Celtic team-mate Darren O'Dea agrees.

"I don't think Celtic will blow Hearts away but I do think they will get the job done," he said on Sportsound. "The energy from the crowd will be through the roof."

Both sides have struggled with injuries throughout this season, and Hearts will be without key defender Craig Halkett and influential midfielder Marc Leonard after both players had surgery on Achilles injuries.

McInnes was able to call on influential duo Harry Milne and Cammy Devlin from the start on Wednesday to replace them, but can they and their colleagues go to the well again - both physically and emotionally - just three days later?

Although he was furious about the decision that led to Celtic's win at Motherwell, McInnes was bullish and is relishing the position his side find themselves in.

"We're delighted to be part of it," he said. "To do it, we're going to have to go and get a positive result. What a game it's going to be."