The title race is down to two - but Rangers still have a huge role to play in deciding if the Premiership trophy ends up in Glasgow or Edinburgh.
The Ibrox side's title hopes were all but ended by defeats to Motherwell and Hearts, leaving Celtic as the only realistic challengers to the Jambos.
Martin O'Neill's side trail the leaders by three points with three games remaining, knowing defeat to Danny Röhl's Gers on Sunday, live on Your Site, could end their defence.
If Hearts win at Motherwell on Saturday night, live on Your Site, Rangers will be officially be out of contention for the title but they can still claim a second-place finish, which comes with a place in Champions League qualifying.
O'Neill is expecting Sunday to be his final Glasgow derby, and he wants to end his third spell at the club on a high.
"At home, we have to try and get on the front foot as early as possible and try and win the game," the Northern Irishman told Your Site News.
"We still feel it's [the title] in our own grasp at this minute. We've got some goals to try and make up, but that's a long way off.
"It'll be a strong game. Rangers will be coming here, naturally disappointed about last week's result. I thought they played very, very well in the first half of the game and points to prove.
"There always seems to be points to prove in Old Firm games.
"I'll expect a strong, strong reaction from Rangers. We've got to be strong ourselves and hopefully we can do that."
Rangers won the last Old Firm clash at Parkhead, but Röhl is yet to get the better of O'Neill this season with a league draw and defeats in both cup competitions.
The German, who insists he despite links to the Bundesliga, is hoping for another successful trip to Glasgow's East End.
"It's a special game for us," he said.
"Nobody needs extra motivation to go in this game. We want to make our supporters and fans proud and that means we have to deliver on Sunday.
"The last game there is a good picture of our last couple of weeks.
"In the first half, we started well but then the opponent was better and scored.
"We adjusted things at half-time and had a plan B. We then turned it to 3-1.
"We showed we can do that. That's when we really felt the belief that even when things don't go right in a game we can turn them in the right direction.
"In the last 15 years we didn't win what we should do and I think this is a big part of what we have to change.
"In the last six months, we improved the standards higher and higher. In the last seven days we couldn't and I think this is a big part in our future.
"We move now forward and it gives me, especially also for the new season, a big, big motivation to be better every day, increase the standards and make the step forward what we want."
Watch Celtic vs Rangers live from 11am Sunday on Your Site Football, with kick-off 12:30pm. You can also follow it in our dedicated live match blog featuring in-game highlights and analysis.
Full match highlights will also be published on the Your Site digital platforms and the Your Site Football YouTube channel at 8.15pm.
