Two managers, both in need of a tonic in their own different ways, left Ewood Park believing that this was a slow-burning affair they should have won.
Sam Allardyce, in his first game back in the stand and – briefly – the dug-out after his heart surgery, saw his side create the majority of the chances when the match came to life in the second half.
But Rafa Benitez, faced with the prospect of a disappointing season fizzling out completely, saw the best chance go begging when David Ngog hit the bar from point-blank range – a contender for miss of the season.
It was, as one interviewer suggested, perhaps a tad indelicately, to Allardyce, "a heart-stopping moment." The Rovers manager said he had felt fine, "apart from the last 10 minutes, when I got a bit agitated."
He was delighted with the performance "and delighted with another clean sheet, but slightly disappointed we didn't win it in the last minute," he said, referring to the second glaring miss of the match, by Rovers' substitute, Nikola Kalinic.
It was a relief to have some misses to discuss after a first half that was barren. Liverpool played Dirk Kuyt as the only full-time striker, in the continuing absence of Fernando Torres, and they lacked anything resembling a cutting edge.
Benitez's other irreplaceable player, Steven Gerrard, was playing his 500th game for the club – only the 13th to achieve that distinction – but his efforts to make it memorable came to nothing. He did have one shot deflected wide and another, shortly before half-time, which had the sting taken out of it by Christopher Samba's tackle, but, for him and the team as a whole, that was just about it.
Blackburn, despite the midweek marathon that brought them the boost of a Carling Cup victory over Chelsea, were even less incisive. Apart from a couple of tolerably perceptive passes from Vince Grella, there was nothing to report but a string of badly executed free-kicks. The loudest cheer was for the welcome news that there was only one minute to add on.
The second half showed tell-tale flickers of life from the start – penalty appeals at both ends, a couple of shots from Gerrard that might have sneaked in during one of his previous 499 matches and a gilt-edged chance for Rovers to take the lead.
The Liverpool defence hesitated, expecting an offside ruling, when Steven Nzonzi's pass put Franco Di Santo through. Perhaps equally surprised, the striker also delayed getting a shot away and Jamie Carragher was able to get back and touch the ball beyond him.
Di Santo did much better with another chance laid on by the industrious Grella, but this time Pepe Reina made a low save.
Then came Ngog's spurned sitter, set up when Glen Johnson surged down the right flank and pulled back a low cross to leave him with an open goal.
"I was convinced it was a goal," Benitez said. The reverberating crossbar indicated otherwise and Kuyt's follow-up was blocked.
The rest of the chances in a much livelier half fell to a Blackburn side showing commendable stamina after their 120 minutes on Wednesday night.
Benni McCarthy failed to react quickly enough when set up by another Rovers replacement, David Hoilett, and Kalinic fired over after a breakaway. He should have scored in extra-time when clean through on Reina, who came out swiftly.
"He had the chance to put the ball in the net and there would have been no time for them to recover," said Allardyce ruefully. At least his own recovery seems well under way.
Referee: Martin Atkinson
Man of the match: Grella
Match rating: 5/10Reuse content