Murray Davidson's first-half double earned St Johnstone their first home victory in five months and left Ross County rooted to the bottom of the Ladbrokes Premiership.

County offered little in response as they fell to a 2-0 defeat and ended the game with 10 men after Craig Curran's late red card.

Saints had only taken one point out of seven matches at McDiarmid Park since beating Hamilton on September 23 and that draw had come in a goalless meeting against County.

Neither side had seriously threatened before Saints opened the scoring with a well-worked goal in the 29th minute.

The hosts took a quick free-kick just inside their own half and got left-back Scott Tanser into a good position on the flank. Tanser delivered a brilliant outswinging cross which Steven MacLean headed into the path of Davidson, who scuffed his shot into the bottom corner from 10 yards.

The Perth side took confidence from the opener and doubled their lead in the 40th minute. Saints worked the ball out wide to Chris Kane and it ultimately fell for Davidson 20 yards out. Scott Fox seemed to have got enough of a hand to the midfielder's looping effort but he could only palm it over his head and into the back of the net.

County were threatening to implode and Marcus Fraser cannoned an attempted clearance off his own bar from six yards after David Wotherspoon had crossed following good footwork from Chris Millar inside the box.

Davidson might have been in for a hat-trick 10 minutes into the second half had Wotherspoon played him through but the former Hibernian player trundled a shot wide from a worse position.

County had used all their substitutes by the 65-minute mark and two of them produced their first shots at goal, but neither Curran nor Mattias Kait could trouble Alan Mannus.

Curran was quickly booked for a foul on Millar after coming on and he was shown a second yellow card in the 84th minute for pushing MacLean after the Saints striker remonstrated with Fraser for not getting the ball back from a throw-in. The hosts had kicked the ball out to allow County midfielder Davis Keillor-Dunn to get treatment for an injury.

Mannus made two decent stops in the closing stages from Keillor-Dunn and Christopher Routis but Saints substitutes Liam Craig and Denny Johnstone both failed to make the most of injury-time chances.