Paul Hayes came off the bench to salvage a 1-1 draw for Preston at Doncaster but hopes of a great escape for Phil Brown's men are fading.
Doncaster led through Brian Stock's 77th minute strike, but the lead was short-lived as Hayes made an instant impact.
Both sides enjoyed a host of chances in an end-to-end affair, while Preston were furious not to be awarded a penalty when Eddie Johnson went down under James O'Connor's challenge in the second half.
Doncaster almost had the perfect start when Stock's perfectly-measured first-time pass found left-back George Friend in the area. Friend let fly with a rasping effort that had Preston goalkeeper Iain Turner at full-stretch to beat over the bar.
Doncaster pressed once more and after Franck Moussa's exquisite 25-yard volley cannoned back off the underside of the crossbar they were in front. Simon Gillett's clever cut-back caught out the massed ranks of Preston defenders and left Stock free to rifle into the top corner from the edge of the box.
Preston sent on Hayes for Johnson and the former Scunthorpe man snatched a quick-fire equaliser as Bongani Khumalo shot against the crossbar and Hayes was on hand to bravely nod home the rebound from a tight angle.