Saffron Jordan and Annabel Blanchard scored either side of half time to give the hosts a commanding lead with substitute Holly Manders’ equaliser igniting hopes of a comeback.
With 90 seconds to go, captain Ramshaw stepped up after Maria Farrugia was fouled in the box, but her well-struck spot kick was brilliantly saved by Alex Brooks as the Black Cats slipped to a disheartening defeat in Lancashire.
Buoyed by last week’s victory over Charlton, the visitors started well, Grace McCatty glancing a header just wide from a tight angle. But Blackburn, one place below Sunderland in the table heading into the game, fought their way back in to the game as the half wore on.
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Jordan, a constant threat throughout, stabbed inches past the far post before her powerful strike from the edge of the area was blocked and gathered by Claudia Moan.
A quick free kick over the top almost caught out the away side’s defence but Moan again was in the right place to deny Megan Hornby.
But, from the resulting corner, Rovers took the lead. Natasha Fenton’s floated ball was headed back across the face of goal and Saffron couldn’t miss as she smashed home from four yards.
Blanchard was next to test Moan as the midfielder tried to sweep the ball into the corner, with her effort was easily saved after being blocked by McCatty.
Sunderland then crafted a couple of chances of their own – Emma Kelly’s corner was headed over by Emily Scarr, Ramshaw’s swerving freekick flashed past the upright and then Maria Farrugia turned smartly on the edge of the box but fired straight at the goalkeeper on the stroke of half-time.
The Malta international had a sight of goal after the interval, jinking her way past several Blackburn defenders only to scuff her shot into the hands of Brooks.
Crompton and Blanchard then tried their luck from distance, with the latter extending her side’s lead on the hour. Jordan won the ball deep in the Sunderland half and played it to the Rovers number 10 who blasted past Moan.
But three minutes later Manders – on in place of the injured Neve Herron – made an almost instant impact. Scarr’s cross bounced up in the area and the midfielder held off a defender to half-volley beyond Brooks.
The comeback was nearly stopped in its tracks as Blanchard found space 25 yards out and delicately chipped over the head of Moan, but the ball bounced off the inside of the woodwork and was cleared.
In the first minute of stoppage time came the late drama. A through pass was fumbled by Brooks into the path of Farrugia who was bundled over by a Blackburn defender. After a long delay as the referee cleared the box, Ramshaw strode forward only to be denied the equaliser by a superb dive by the goalkeeper to her right.
It was yet another disappointing defeat for Sunderland but are now only one point away from the season’s target of playing Championship football next season.
Sunderland: Moan; Griffiths, Towers, McCatty, Brown; Kelly, Herron (Manders 67’), Joice; Scarr, Farrugia, Ramshaw.
Subs: Cowling, Boyes, Mullen, Blakey, Ede, McInnes, Watson, Burt.