document: The Premiership leaders head to Ibrox for the first time this season having won 5-1 at Celtic Park in September and 1-0 at Hampden Park in the League Cup.
  "I think we have progressed since that game, I think we have been even better.
  "So if you take that into account, it might be that the gap is bigger," said the Dane ahead of Saturday's clash.
  "You always talk about gaps but you also know that one game can change that perception of it.
  "So I think the most important thing is to be respectful and say that we are doing our job and Rangers are doing their job.
  "If we at the moment are number one that means something, so we will be doing our best to keep that."
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  Rangers have taken 24 points from a possible 33 since their League Cup semi-final defeat to move into second place in the Premiership, having won four and drawn one of their last five games.
  "They have improved, for sure," Sviatchenko acknowledged. "It is always difficult to come back up into the league but they have performed well and you can see that in the table.
  "But I think we are still doing really well and we need to focus on ourselves."
  Celtic, chasing a sixth successive league title, are unbeaten in 23 domestic matches this season and have won their last 14 matches in the Premiership.
  They are within three matches of equalling the club's 'Lisbon Lions' class of 1966-67 that went 26 domestic matches unbeaten at the start of the season - before losing 3-2 at Dundee United on 31 December.
summary: Celtic defender Erik Sviatchenko believes the gap between the champions and Rangers may have grown since their last meeting two months ago.