Dennis Wyness opened the scoring for Inverness

Dennis Wyness fired the opener after two minutes when David Cowan's push on Ross Tokely led to a penalty kick.

Don Cowie curled in the second from a 25-yard free-kick that deceived debutant goalkeeper Tony Caig.

Barry Wilson fired in from close range and Roy McBain from long range after the break to leave Gretna bottom.

Interview: Gretna head coach David Irons

Interview: Inverness CT player-manager Craig Brewster

Inverness and Gretna had both changed their goalkeepers in front of 1,020 fans in Motherwell - the lowest-ever attendance at a Scottish Premier League game.

Inverness recalled Michael Fraser after Zibi Malkowski's costly mistake last weekend.

Gretna handed Caig his first start since joining the club as an amateur following his exit from Vancouver Whitecaps, with Greg Fleming missing out for the first time this season.

Ryan McGuffie, Mikael Buscher and Steven Hogg also came in, with James Grady dropped, Craig Barr suspended and skipper Chris Innes injured.

And Caig's first task was to face a penalty.

Cowan gave away the spot-kick in the second minute for a push on Tokely as Gretna defended a long throw.

Wyness sent the former Carlisle goalkeeper the wrong way to net his seventh goal in as many games.

Inverness were the more accomplished team in possession and looked threatening whenever they moved forward, although it took 20 minutes before they worried Caig again.

Marius Niculae broke from the halfway line before stopping and turning 25 yards out and driving a low shot just wide of the far post.

Don Cowie grabbed the second goal from a free-kick

Gretna had to shoot from 35 yards for their first effort on goal, but Fabian Yantorno's free-kick dropped harmlessly on the roof of the net.

Danny Grainger came to Caig's rescue by clearing a Niculae volley off the line after the goalkeeper had failed to collect a high ball.

But the goalkeeper looked slow to react when Cowie curled a 25-yard free-kick around the wall and inside Caig's near post after 31 minutes.

McBain drove a powerful effort just beyond the far post after a deep corner as Inverness remained in complete control up to the break.

Gretna boss Davie Irons brought on David Graham for Cowan and switched to a three-man defence.

But Inverness started the second half as they had finished the first, Niculae, Wyness and Ian Black all going close.

Yantorno squandered a chance for Gretna, while Gavin Skelton forced a good diving save from Fraser from his long-range effort.

But Inverness ended hoped of a revival after 72 minutes when Wilson fired home from six yards after a fine move involving Phil McGuire and Grant Munro.

McBain added the fourth two minutes later to complete Gretna's misery by drilling the ball home in off the bar from 30 yards.

Gretna: Caig, Cowan (Graham 46), McGuffie, Horwood, Grainger, Jenkins, Murray, Hogg (Grady 66), Skelton, Yantorno, Buscher (McMenamin 79).
Subs Not Used: Fleming, Paartalu, McGill, Deverdics.

Booked: Murray.

Inverness CT: Fraser, Tokely, McBain, Munro, McGuire (Proctor 79), Hastings, Black (Wilson 60), Cowie, Duncan, Wyness, Niculae (Bayne 72).
Subs Not Used: Malkowski, McDonald, Kerr, Vigurs.

Booked: McGuire.

Goals: Wyness 2 pen, Cowie 31, Wilson 73, McBain 75.

Att: 1,020

Ref: M McCurry