Rangers 1-1 Albion Rovers
Albion Rovers' Scottish Cup dreams remain alive after they took Rangers to a replay.
Ciaran Donnelly volleyed the visitors in front and for long spells it looked as though they would book a return trip to Ibrox in the semi-final.
Rangers could not break down the visitors and it took until 13 minutes from time until Bilel Mohsni knocked in a contentious equaliser.
Albion Rovers had to withstand heavy pressure but more than earned a draw.
The two teams will have to do it all again in ten days' time when they go head-to-head at Hamilton Academical's New Douglas Park.
Rovers showed they had not arrived in Glasgow to simply make up the numbers when Liam Cusack fired wide from the edge of the box as early as the second minute.
That was just a warning shot, but they silenced Ibrox when they tore up the script and took the lead.
Lee McCulloch's attempted clearance from a corner was poor, sending a header back into the middle where Donnelly was able to find space amidst a flurry of bodies and volley the loose ball into the net from close range.
Rangers' initial response was slow, and it was only as half-time approached that they looked likely to unlock the visitors' rearguard; David Templeton twice firing in efforts from distance before Dean Shiels' drilled shot forced a low save from Neil Parry.
The pressure from the home side was cranked up after half-time. McCulloch, Jon Daly and Richard Foster were all off target from inside the area, and Templeton hit the bar.
As Rangers huffed and puffed, Rovers had the semi-final in their sights when the home side finally drew level in controversial circumstances.
When Mohsni went up with the goalkeeper for Templeton's deep cross the ball appeared to evade both as it found its way into the net.
The Coatbridge men were adamant it was a foul on Parry, but referee John Beaton awarded the goal and Mohsni was credited as the scorer.
Fraser Aird fired over as Rangers chased a winner, then Mohsni headed wide at the back post.
The home side continued to press. Parry was forced into saves from McCulloch and Templeton as the clock ticked into injury-time and Ally McCoist's side could not grab a winner.