Celtic manager Martin O'Neill has warned his side are running out of games in the race for the Scottish Premiership title ahead of Saturday's visit of fellow challengers Motherwell.
The champions trail league leaders Hearts by five points, with rivals Rangers one point further back, and surprise packages Motherwell 10 off the top.
O'Neill's side have come through a gruelling run of four consecutive away matches in just 10 days, which included back-to-back visits to the home of their Old Firm rivals.
They came from 2-0 down to earn a 2-2 draw at Ibrox in their league meeting two weeks ago before progressing to the semi-finals of the Scottish Cup with a penalty shoot-out victory on Sunday .
With only nine games remaining, O'Neill understands there is little room for error left in their title defence.
He said: "It's crucial in every aspect because you're running out of games.
"We couldn't afford to, if I looked at it really properly, I don't think that we could drop too many points and still think we could possibly win the league.
"It would be very difficult to do that with the games running down."
Motherwell visit Celtic Park with the chance to move within two points of the champions and may yet fancy themselves as outsiders for the title.
Despite failing to cut the gap on Hearts to seven points when they lost to Dundee last weekend, Jens Berthel Askou's side remain one of the most dangerous and defensively astute sides in the league.
Nobody in the Scottish Premiership, or even Europe's top five leagues, has conceded fewer goals [20] or kept as many clean sheets as Motherwell [16].
But it is their offensive prowess that has impressed O'Neill the most.
He added: "A really tough game, absolutely. They've had a fantastic time, a bit of a setback there last week at Dundee, but really have been the proverbial breath of fresh air for the Scottish Premiership.
"It's been terrific, they've played really well and they play matches without any real fear.
"It's great and it's been terrific for them. They've been terrific, Hearts have been great this season and I also think that Falkirk have been terrific as well.
"But from our immediate opponents, Motherwell, yes, a real difficult game for us."
Celtic remain without captain Callum McGregor, but O'Neill is hopeful this will be his last match on the sidelines. Kieran Tierney is set to return after a foot knock, while Kasper Schmeichel is nearing a return after having an injection on his shoulder.
Meanwhile, the Celtic boss still expects away fans to attend the next Old Firm league fixture at Celtic Park, despite crowd trouble following their Scottish Cup victory over Rangers last weekend.
However, O'Neill conceded that he fears the larger away allocation of nearly 7,500 tickets permitted on Sunday will "disappear" due to the violent post-match scenes.
He said: "The saddest part about it all is that, of course, you don't want anybody injured for a start, although I think there were some scenes outside the football club, but to me, the idea then that the full allocation of tickets looks as if that will disappear again.
"That's something that, as I said to you then, I would like to have seen, and I assume that because of those scenes, it probably won't happen.
"Rangers will be due their allocation, won't they? And they're entitled to that as well too.
"It's a league game, so I don't think anybody's arguing about that, but what I was talking about was the full allocation, something that I feel the fixture, although still a great fixture, has missed in years.
"And it looks, because of the happenings on Sunday, I assume that everybody will have a look at it and think, well, maybe it's not worthwhile."
