Last updated on .From the section Football

St Johnstone striker Stevie May took his season's goal tally to 15 as his hat-trick inflicted defeat on Tayside rivals Dundee United at McDiarmid Park.

But there has been little season's cheer for United boss Jackie McNamara as his decision to make eight changes failed to prevent consecutive losses.

United were under the cosh when Calum Butcher was sent off for a foul on May who slammed home the penalty.

In the second half May twice fired past Radoslaw Cierzniak to cement the win.

United had been beaten 4-1 on Boxing Day by St Mirren and McNamara's raft of changes were designed to rediscover the superb form of the previous seven weeks.

Saints, who had not scored in their last four matches, took the lead in 20 minutes.

Butcher was red carded for denying an obvious goal-scoring opportunity with a tackle on May in the box and the Saints striker converted with a powerful low shot.

The sending off forced McNamara into removing striker David Goodwillie in favour of defender John Souttar.

Murray Davidson almost doubled Saints' advantage five minutes later but his header was booted off the line by United defender Andy Robertson.

The pressure on the United goal was intense but Mark Wilson did at least give the Perth side cause for concern when he fired in a free-kick which was a yard wide of Alan Mannus's post.

However, St Johnstone continued to dominate and they ended the half against United with a one-goal lead.

May added Saints' second and his 14th of the season nine minutes into the restart, firing the ball low under Cierzniak from an acute angle on the left side of United's 18-yard box.

Just before that, Wotherspoon had stung Cierzniak's hands with a fierce shot, but Saints' reward was only delayed by seconds.

Dundee United's Brian Graham powered a header over the bar from six yards in 77 minutes as theytried to claw their way into the game, but Saints almost added a third when Nigel Hasselbaink raced down the left and shot across the goalmouth to miss by inches.

May added his and Saints' third in the final minutes with a beautiful clipped shot from six yards to finish off a perfect low cross from Gwion Edwards.