Liam Boyce bagged four goals as Ross County won the Highland derby to increase Inverness Caley Thistle's relegation fears.

The striker pounced on keeper Ryan Esson's error to net the opener and made it 2-0 with a brilliant header.

Boyce scored twice from the spot after the break, with ICT's Liam Polworth sent off for giving away the second.

The result leaves bottom-of-the-Premiership Inverness five points behind Dundee with four games to play.

County, meanwhile, move up to seventh spot on 36 points, one above Kilmarnock who visit Hamilton on Saturday.

Buoyant Boyce

The Northern Irishman takes the plaudits once again with his quadruple dismantling Inverness and propelling County away from relegation concerns.

His opener was opportunistic as he sensed the possibility of an error which duly arrived.

His header for the second was superb. It was a great run before a stretch of the neck allowed him to meet Jim O'Brien's delivery and nod over Esson.

Boyce then brilliantly converted two penalties as he almost extinguished Inverness' survival hopes single-handedly.

David Raven clumsily bundled into Tim Chow for the first spot kick and Polworth pulled Ryan Dow back and was sent off.

It was a memorable night for Boyce and Ross County. One to forget in a season to forget for Inverness.

Doomed?

Not quite, but close. Richie Foran's side are snookered and cannot buy a break, although they undoubtedly contributed to their own downfall.

Things looked bright early on as the visitors controlled the opening quarter. Crucially, however, they could not capitalise before Esson, who was playing because of an injury to Owain Fon Williams, made a horrendous error that undermined his side's game-plan.

A Jamie McCart back-pass was not the easiest for the keeper to deal with but he still had to do better than fluff his attempted clearance, leaving Boyce with the simple task of finishing.

It became watch-through-the-fingers stuff for Inverness fans with their main weakness, defending, exposed once again.

No-one challenged Boyce for his second with the third and fourth goals conceded so cheaply.

Inverness may point to a penalty claim when two goals down as Tim Chow appeared to push Polworth to the ground but other than that they offered very little.

The main surprise was County failed to add to their tally when Inverness were down and out.

What next?

The latter stages of the game were like a training match for County, who can relax to an extent in the knowledge they are mostly likely safe, and can now focus on trying to secure seventh spot.

Everything went wrong for Inverness. They have only won four games this term and this result will give their confidence another kicking.

It is not over yet but Foran requires a remarkable turnaround if Inverness are to avoid relegation.