Hearts fans endured an agonising derby at Easter Road before emerging victorious.

Watch: Hibernian v Hearts highlights.

One by one, the maroon waves started washing towards the away end at Easter Road. In victory - late and glorious and possibly historic - Lawrence Shankland ran towards the Hearts fans and punched the air, an afternoon of frustration and relief pouring out of him and those around him.

This was a battle, an unmerciful grind against 11 Hibs players, then 10, then nine. The more men David Gray's team lost, the greater their resolve became. Backs to the wall, utter defiance, questions posed and questions answered. Eventually Hearts broke them.

Derek McInnes threw subs into the maelstrom and those subs delivered in the most spectacular way - Sabah Kerjota heavily involved in the equaliser and the winner, scored by Blair Spittal, another member of the bench cavalry. McInnes saluted Kerjota for his guile in taking players on and unlocking a defence that at times made you think that a miraculous act of escapology was possible.

Hearts endured and they are three points clear at the top with four games to go. They have Rangers next. Tynecastle awaits. A fortress.

In the three-horse race Rangers were the first to hit a hurdle, losing at home to Motherwell. Their hopes are hanging by a thread now. Hearts can effectively finish them on Monday week.

Late winner moves Hearts three clear with four to play after chaotic derby. Latest Hearts news, analysis and fan views. Get Hearts news notifications in the BBC Sport app.

This was a monumental test of Hearts' mettle and they passed it, with a world of help from Hibs and their self-destructive red cards. Look up a thesaurus and you'll find dozens of ways to describe what happened here but, somehow, none of them quite hit the mark.

The whole business was entirely in keeping with the season, the twists and turns and stings in the tail. Sensation is no stranger to this rivalry. Heart-stopping stuff. Bedlam.

Craig Halkett's 90th-minute winner at Tynecastle in October. Raphael Sallinger's spectacular save from Shankland to deny Hearts an injury-time draw in December. Tomas Magnusson winning it in the 88th minute in February.

When it comes to these two, you learn to hold on before making any big calls, particularly Hearts. From the 83rd minute onwards in all league games this season, they've mined 20 points. Twenty. Last-gasp winners. Late, late equalisers. Never over until it's over. You can make that 23 now. It's an almost unfathomable statistic.

Here, both sides decided to get down to it from the get-go. No feeling their way in, no shadow boxing. With Hearts going for the title and Hibs busting a gut to derail them, there was a school of thought that this was the biggest Edinburgh derby of them all in the league. And it felt like it. Boy, did it fizz and crackle.

Seven minutes in and Martin Boyle scored. His last derby and there he was, writing his own farewell script. Or so he would have hoped. Jamie McGrath's vicious free-kick, Beni Banigime dozing and in rushed Boyle - cool and calm, a sidefoot to the solar plexus of the visitors. Down the Hearts end, too. A perfect view of their nightmare start. Easter Road basked not just in the sunshine but in the anxiety of their guests, the unspeakable horror of having their league dream buffeted by their greatest rivals.

What unfolded was pulsating, a red card for Sallinger only four minutes after Boyle scored, a daft act of handling the ball outside his own area and a call that was easier to make than the officials made it look. Everybody knew that Sallinger was goosed on first, or second, viewing. The officials took five or six minutes. It was a calamity for Hibs.

The mood completely shifted and shifted some more when the news came through that Rangers had blinked first in the title race. Later, McInnes spoke of the importance of winning your first post-split game and he was right. Hearts and Celtic are now on the front foot.

There was a manic feel to Hearts' pursuit of an equaliser. They owned the ball. Before the half was done they had 74% possession, 13 shots, 29 touches in Hibs' penalty area - their hosts had two - and 21 crosses to Hibs' one. Their panicky nature was understandable but self-harming. They were running around like mad dogs in a meathouse and lacking accuracy as a consequence. They were excitable - McInnes' word. Hard to blame them. The stakes were sky high, the sense of frustration in the face of Hibs' dogged resistance so palpable you could have reached out and touched it.

Another wow! moment just after half-time. Felix Passlack, a feisty and impressive operator in the rearguard battle, lost the run of himself. Already booked, he caught Baningime above the knee and off he went. Hibs down to nine.

Once again this season was finding new, and exhilarating ways, of getting the pulse beating at an unhealthy rate. Hearts pummelled Hibs thereafter. Shots and crosses, blocks and headers. For every attack, Hibs had a response. Braga went through one-on-one but Smith saved. Halkett lashed one from distance, Smith saved again. Marc Leonard, summoning every ounce of venom he could muster, thumped one on goal and it came slapping back off the crossbar.

'Title not won or lost today, but this is big' - Scottish Football Podcast.

Eventually, the Hibs dam burst. It had to. What they were doing out there was almost unnatural, their ability to soak up the punches and stay on their feet.

When McInnes put Kerjota into the fray he would have hoped for - but not have imagined - the impact he was going to have. He knew what the player was capable of but he didn't know how he was going to handle the heat.

He was heavily involved in the equaliser. Confident and aggressive, he took it to the bye-line and from his cross, Warren O'Hora turned it into his own net under pressure from Shankland. When Kerjota did the same again with five minutes to go, it was the salvation of his team, a ball into Spittal and a winner. Another late one.

Another moment that made you wonder about fate and destiny. A heart-breaker for the hosts, for sure. They couldn't have done much more. Undone by their own ill-discipline, a shot at damaging Hearts' dream lost on the back of two ruinous decisions. Spittal's goal, driven in with gusto, could form a part of Scottish football history in a few weeks time.

There's much work to be done, of course. Four games left - all winnable, all loseable. Their story continues just as the chase carries on for Celtic and a wounded Rangers. To those who didn't believe that Hearts were capable of going the distance, the question must be posed - do you believe in them now?

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