Celtic are currently 16 points behind their rivals
Celtic are trailing by a significant margin in the title race, but James McFadden says they should forget about the side above them in the table.
Rangers have established a 16-point lead after going unbeaten in their opening 20 Premiership matches, while Celtic have endured a number of disappointing results.
The champions have three games in hand, however, and can work their way back into the title race with a win at Ibrox on Saturday.
Scotland legend McFadden believes Neil Lennon’s side should focus only on what they can achieve, rather than thinking about their rivals.
The former Motherwell and Everton man has pinpointed the key partnership that he believes can spearhead Celtic’s title comeback.
Speaking on Sky Sports, McFadden said: “I don’t think there’s any margin for error for Celtic.
“They have to keep winning, forget what’s happening with Rangers.
“They can hope they drop points of course but they need to make sure they’re winning games.
“They are on the right track and their form is picking up.
“The introduction of (Odsonne) Edouard along with (Leigh) Griffiths last season will prove crucial for them in order to win games.
“David Turnbull has been magnificent since stepping into the side and they are improving.
“It’s all about building towards this big game at the end of the week.”
Edouard, who has been linked with Milan and Juventus in recent weeks, partnered with Griffiths to great effect in Saturday’s 3-0 win over Hamilton Accies.
Celtic host Dundee United on Wednesday night as they aim to secure a fourth consecutive Premiership victory.
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