St Johnstone captain Dave Mackay is out for the rest of the season

St Johnstone captain Dave Mackay will miss the rest of the season due to further problems with his hip.

The Saints defender had an operation to rectify the problem last summer and missed the start of the campaign.

While the 34-year-old appeared to have recovered from his operation, he has been troubled by the problem once again and requires further surgery.

St Johnstone manager Tommy Wright insists the club had no choice and expects the player will be available again for the start of next season.

Wright said: "Dave's been able to manage the problem since returning to action but he has been in a lot of discomfort this week and so we sent him for further consultation and the outcome is that he needs another operation.

"He's looking an absence of four to five months so unfortunately his season is over. I'm very disappointed for him because he put a lot of work into his recovery back in the summer and autumn."

The Saints boss has wasted no time in bringing in defensive cover and has signed former Kilmarnock and Alloa right-back Michael Doyle.

And the 24-year-old, who also had an opportunity to move join Cork, will go straight into the squad for Saturday's visit of title-challengers Aberdeen.

Wright said: "I know Michael well. He was about to sign for Cork City but wants fulltime football in Scotland and this opportunity has come up at the right time for him.

"He's a good athlete and experienced and will give us good cover at a critical stage in the season."