The Scottish title race will be over if Celtic win Sunday's Old Firm clash, according to former Hoops midfielder Paul Hartley.
Leaders Celtic will go 13 points clear of second-placed Rangers with seven games to go if they win at Parkhead, live on Sky Sports.
Speaking at an event focusing on the SFA's Mental Health and Wellbeing League, Hartley said Rangers must get three points to stay in touch at the top.
"They've got to win," Hartley told Sky Sports News. "Ten points behind, eight games to go, they've got to go there and try to win the game.
"There's no point in going there and trying to sit back. Celtic can afford the draw but they'll be going to try to win the game. If they win it looks like that's the title over.
"Rangers know they can't afford any more slip ups. They are out of both cups, they may not have any more silverware for another year so it's a massive game for them."
Hartley has been impressed with the way Celtic have maintained their form after Neil Lennon returned to the club in February to take over from the departed Brendan Rodgers.
"They've had to grind a couple of results out," he added. "They won at Tynecastle and at Dundee but that shows they're a good team, they can grind out different results and play in a different style.
"He's had a good start since he's come back in, but Sunday's the big one for both teams.
"Rangers deserved to win the last game, Celtic will try to make amends for that."
Hartley was asked if he thinks Lennon has done enough to get the job on a permanent basis.
"He knows the club," Hartley said. "He's been there as a player, as a coach and as a manager. I think if Neil wins the league and the Scottish Cup then he's done his chances no harm whatsoever, but that will be up to the people above.
"All Neil can do is win as many games as he can. If he wins the league and the cup then he's done a terrific job."
Paul Hartley was speaking at an event focusing on the SFA's Mental Health and Wellbeing League, which aims to promote positive mental health and provide support for those affected.