Inverness feel the full four-ce of Liam Boyce in derby defeat to Ross County

Liam Boyce nudged Inverness closer to the drop with a four-goal salvo in an impressive Ross County display in the Highland derby at Global Energy Stadium.

Boyce struck twice in the first half and added a couple of penalties after the break as County strolled to a victory which moved them 11 minutes clear of their local rivals.

Caley Thistle ended the 4-0 defeat with 10 men - Liam Polworth was sent off after conceding the second penalty on the hour mark.

The visitors forced the first corner of the match in the fifth minute and when Iain Vigurs' inswinger fell for Alex Fisher at the back post the striker failed to control the ball and the chance was lost.

County midfielder Jim O'Brien became the first player in to the book of referee Craig Thomson for a late tackle on David Raven.

A good run down the left by Ryan Dow produced County's first corner of the match but O'Brien's ball into the box was headed clear by Raven.

Good link up play on the other side of the park set Michael Gardyne free on the right but his cross into the area was missed by both Inverness goalkeeper Ryan Esson and Boyce.

However, the visitors threatened almost immediately and a dangerous ball in by Jake Mulraney was headed clear by Tim Chow.

It was end to end stuff and O'Brien forced a clearance from Kevin McNaughton before Martin Woods blasted a shot over the crossbar.

But the home side opened the scoring in the 21st minute when Esson got into difficulties in trying to deal with a Jamie McCart backpass. The keeper got caught on the ball and Boyce took full advantage before slotting the ball into the empty net for his 18th goal of the season.

County pushed for a second and O'Brien picked the ball up on the edge of the 18-yard box after a Woods free-kick was only partially cleared - but his effort cleared the crossbar.

The pressure paid off in the 34th minute when O'Brien kept the ball in play and his cross back into the box was met by Boyce, whose glancing header flew into the far corner of the net.

The home side almost made it 3-0 three minutes later when Gardyne swung the ball into the danger area but Boyce failed to get enough power in his shot to beat Esson, who saved comfortably.

County made the perfect start to the second half when they were awarded a penalty in the 49th minute when Raven brought down Woods inside the box. Boyce sent the Esson the wrong way from the spot.

The visitors tried to get a foothold in the game and good work from Mulraney set up substitute Henri Anier with a chance - but his effort was blocked.

However, it was 4-0 in the 60th minute when the home side were awarded a second penalty after Ryan was taken down by Polworth.

The Inverness player was shown a red card and Boyce scored again from the spot for his ninth derby goal of the season.