There will be a late fitness test for St Johnstone defender Brian Easton.
The former Dundee man missed last weekend’s match against Aberdeen with a leg gash, but Tommy Wright is hopeful the left-back will be available to face his former club.
Even if he is though, the Perth boss will have a tough decision to make given how well Tam Scobbie played in his absence last Saturday.
“Easty’s fitness levels are good and we will have to see how he is striking the ball,” Wright, who welcomes Murray Davidson back from suspension, reported.
“The two full-backs were excellent against Aberdeen and bar the third goal the defence was pretty good. So that gives me something to ponder.
“Dave Mackay has seen the specialist who carried out the original operation for a second opinion. The surgery will probably go ahead next week.
“Murray is a fit lad but he actually had a moan about being victimised in training this week. He has great energy levels and I think we missed his physical presence last week. I’m glad to have him back for the derby.”
Wright added: “The Hearts win over Ross County in midweek was good for us and Dundee.
“We have matches in hand on County and the games before the split are vital. Every point is important because it can take you clear of teams.
“Both sides will be going all out for the win. We know we can go fourth with a victory and they can overtake us if they win.
“It is set up for a decent game and there will be a good atmosphere. Hopefully it is a good spectacle but we just want three points.”