Alex Baptiste then had a goal-bound header brilliantly saved as Blackburn continued to impress after the break.
Liverpool pressed late on with Jordan Henderson seeing a volley saved, but a replay at Ewood Park now awaits.
The match was halted for eight minutes early on as centre-back Martin Skrtel was taken off on a stretcher with a head injury after a heavy landing following a aerial challenge with Rudy Gestede.
Liverpool skipper Steven Gerrard was denied an Anfield FA Cup farewell, after being left out of the squad following six matches on the sidelines with a hamstring injury, but retains hope of a dream finale come 30 May.
The 34-year-old, who will leave Liverpool for LA Galaxy in the summer, has lifted the trophy twice for the Reds and this year’s final – which would be his last game for the club – falls on his 35th birthday. The Reds will have to play better in the replay if they are to reach a Wembley semi-final, though, as Rovers soaked up early pressure to hit them on the break, with striker Gestede a real threat.
The visitors’ confidence mirrored that shown in victories over Premier League Swansea and Stoke en route to reaching their second FA Cup quarter-final in three years.
And with Gestede dominating the hosts in the air early on, there were signs they could repeat their Anfield FA Cup heroics of 2000 when Nathan Blake scored to knock them out in the fourth round.
Rovers are 14 points off the play-off places in the Championship but Champions League-chasing Liverpool were struggling to cope as Conway and Gestede went close.
Liverpool, seeking their first FA Cup triumph since 2006, were thankful to goalkeeper Simon Mignolet’s stunning save to keep out Baptiste’s header after the break.
The inevitable home pressure finally came as the match clock ticked down, but Liverpool, who also drew 0-0 with Championship Bolton earlier in the competition, were unable to break their visitors down and must hope they can get the job done at the second time of asking. courtesy:bbc.co.uk