Billy Mckay broke his arm as he completed a hat-trick to keep relentless Ross County five points clear at the Championship summit with a game in hand.

It proved an incredible end-to-end battle with Ayr United, who fell eight points behind the leaders, who have a game in hand. The Honest Men levelled twice but slipped to costly defeat as their 2019 nose-dive continued.

Mckay’s treble took him to the 20-mark for the campaign and left County unbeaten in eight matches, including six victories and two draws.

Inside the first minute, the hosts forced a corner and a fantastic save from Ayr goalkeeper Ross Doohan.

Josh Mullin’s delivery found young Tom Grivosti steering a header inside the right hand post, only for the on-loan Celtic keeper to tip it just wide.

Early County pressure gave way to a good spell for Ayr, though, with a Robbie Crawford strike deflected for a corner.

Soon after, Michael Moffat’s weighted ball over the top found Lawrence Shankland pulling a shot just wide from the right of the County penalty area.

The Staggies were dealt a blow after 22 minutes as Ross Stewart, with four goals in his last four games, hobbling off injured to be replaced by Brian Graham.

A fine Gardyne pass after 26 minutes slipped Mullin clean away in the box but Doohan again rose to the occasion with a strong block from 12 yards.

With Mullin rippling the Ayr side-netting soon after, home momentum was building.

More followed with a searing Gardyne run and one-two exchange with Billy Mckay ending with a rising Gardyne strike from 18-yards palmed over the bar.

Sure enough, the breakthrough came after 35 minutes.

Jamie Lindsay’s looping high ball into the box was expertly controlled by Mckay and tucked past Doohan with ease from six yards.

It could have been two for County on half-time as Mullin clipped the top of the bar from 12 yards from Gardyne’s cut-back.

The second half was a slow-burner – but would soon ignite.

Approaching the hour, on-loan Celtic wide man Calvin Miller cut inside to test keeper Scott Fox with a venomous attempt. Fox blocked before the ball was hacked clear.

That was merely a warning. Ayr were level two minutes later as Liam Smith took a Shankland pass to race past Jamie Lindsay in the home box.

The cut-back found Shankland with abundant time to slam in his 31st goal of the season from eight yards.

Play raged end-to-end as County’s Mckay drew another Doohan block close-in and Calvin Miller cut another attempt onto the roof of the net.

But County went ahead again on 70 minutes as Mckay took a Lindsay pass on the edge of the penalty area and thrashed a tremendous finish high past Doohan to his left.

Ayr hit back inside four minutes. A Shankland cross from the left was scooped up by a sliding Michael Moffat for Andrew Murdoch to head home close-in.

Remarkably, though, the Ayr equaliser was wiped out when Keith Watson’s header from a County free-kick was saved by Doohan.

Mckay, for his hat-trick, slid in to score but broke his wrist as he landed awkwardly and exited immediately after in agony.