Motherwell have been warned that Celtic will be aiming to turn in their best performance of the season at Fir Park this weekend.
The Steelmen face a huge challenge this weekend against a Hoops side who swept past rivals Rangers 3-0 on Wednesday to top the Premiership table.
Graham Alexander's 'Well side meanwhile are yet to win in the league post winter-break but remain in the league's top four.
Despite the convincing win over Rangers, Celtic boss Postecoglou says that his team need to keep improving. That starts with their best display of the season at Fir Park.
He said: "We go into every game, whether that is Wednesday night or on Sunday, saying to the boys, 'okay, the main objective will be to play our best game of the season today - let's play better than we have played so far'.
"So you are not thinking about how we played in the last game, that it was good and we want to repeat that. We don't want to repeat that, you want to improve on that.
"It doesn't always work out like that, sometimes there is a dip in form, sometimes the opposition can stop you from playing at those levels but in terms of the intent, of course you want to improve.
"There has to be improvement, we have to improve, absolutely. Motherwell are a good side with ambitions to stay in the top half of the table. They'll test us."
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