Liverpool's third-choice goalkeeper Brad Jones found himself thrust into the spotlight for all the wrong reasons but Andy Carroll ensured he was not alone as the £35million striker snatched a stoppage-time winner.
Alexander Doni, deputising for the suspended Jose Reina, was sent off midway through the first half, meaning Jones had to make his Premier League debut just four days before the club's semi against Everton.
He had a mixed night, saving the penalty conceded by his predecessor but making a mess of a backpass and fouling Ayegbeni Yakubu to concede the second-half spot-kick which brought the equaliser.
The Australian, who had made just two previous appearances since being signed by Roy Hodgson in the summer of 2010, is now the only senior goalkeeper available to manager Kenny Dalglish for Wembley - which remains the club's priority despite a first league win in five league matches.
Jones is unlikely to be a great believer in fate, having tragically lost his five-year-old son Luca to leukaemia in November. He became a father again to another boy, Nico Luca, exactly a week ago.
He could not have imagined the night - or the week he was in for - after Maxi Rodriguez's two goals put Liverpool in command after just 16 minutes.
However, after saving a penalty he was twice beaten by Yakubu - who took his tally to 16 in the league - only for Carroll to rescue him and Liverpool with the winner two minutes into four minutes of added time.
Rodriguez, a bit-part player at best under Dalglish, made it four goals in just eight league games this season - and 14 in his last 20 appearances in all competitions going back to last April.
Martin Skrtel's long ball from well inside his own penalty area reached Craig Bellamy on the right and he charged forward before delivering an inch-perfect cross for the Argentinian to convert with a trademark close-range finish.
Rovers barely had time to recover before he struck again, having benefited from the industry of Jonjo Shelvey.
The Liverpool midfielder robbed David Dunn and ran 50 yards to force Paul Robinson to parry his low shot into the path of Carroll.
His effort was blocked by Bradley Orr into the path of Rodriguez, but once again the Reds' little Argentinian was in the right place at the right time to smash in a first-time volley with his weaker left foot.
But Liverpool's season has been anything but straightforward, winning the Carling Cup but seeing their league form take a dive, and events in the latter stages of the first half proved that.
Jon Flanagan, who had already been booked for fouling Marcus Olsson, left a backpass hopelessly short and Junior Hoilett seized on it only to be brought down by Doni, who was immediately shown the red card.
April 10 holds bad memories for Doni as exactly five years ago he conceded seven playing for Roma against Manchester United.
Jones, with one appearance apiece in the Carling Cup and Europa League last season, was brought on for Flanagan with effectively 65 minutes to prepare for Wembley having last played for the first team in December 2010.
He began well, however, by saving Yakubu's weak penalty but was beaten 11 minutes into his Premier League debut when the unmarked Yakubu headed in Dunn's free-kick after Bellamy had needlessly handled.
Jones spent much of the half-time interval getting some much-needed practise but at the start of the second half Liverpool's familiar problems resurfaced once more as Carroll headed wide Bellamy's corner from three yards at the far post.
The work during the break did not seem to have helped Jones much, however, as when he smashed Skrtel's backpass straight at Yakubu he palmed away the looping ball instead of catching it and in attempting to recover he brought down the Nigerian.
Referee Anthony Taylor was lenient in showing a yellow card but Yakubu was less so, drilling his spot-kick straight down the middle.
Jones redeemed himself by tipping over Carroll's defensive backheader as Blackburn ended the game making all the running, with their need for points far greater.
But for once it was Liverpool who snatched all three points as substitute Daniel Agger flicked on a cross and Carroll powered a header past Robinson to keep Rovers in the bottom three.