Mark McGhee believes his Motherwell side must pick up at least a point against Celtic if they are to secure a top six Premiership finish.

The Steelmen can finish in the top half of the table ahead of the split should they claim a victory, but St Johnstone, Dundee, Partick and Ross County are all in the race for top six place after the split.

Last week's win over Inverness in the Highlands boosted their chances of achieving that objective, but McGhee still believes his team must pick up a positive result against the league leaders this Saturday.

"[The win over Inverness] reinforces what I said at the beginning of the week, that we are going to need something against Celtic on Saturday morning.

"You can't trust anyone in this league, everyone's capable of beating everyone else.

"I think that if we don't get anything on Saturday morning we're in trouble, because I think the mentality of the other three teams will be good enough to get wins.

"I've never allowed myself to get in any other frame of mind."

McGhee confessed his concern over Leigh Griffiths' stretch of three games without a goal, commenting: "He doesn't go long without scoring a goal.

"I think we're going to have to score a goal more than them because they are due a goal.

"He's a fantastic finisher, if you give him any sight of goal at all... he hits the ball very hard, he's very accurate, he's consistent in his finishing, you just can't give him an opportunity.

"You have to stop the ball going to him."