Fred Onyedinma struck early in the second half as bottom club Wycombe won for only the seventh time in the Championship this season, beating Blackburn 1-0.
It gave the Chairboys a glimmer of hope in their battle to avoid the drop as Blackburn's winless run was extended to five games.
Wycombe were on top in the early stages and came close to taking an early lead as Uche Ikpeazu found space from Curtis Thompson's ball, but his effort was deflected wide by Joe Rankin-Costello.
The hosts were hit by an early injury to Dominic Gape who was taken off on a stretcher.
But they went close again as Admiral Muskwe headed wide right in front of goal from Joe Jacobson's corner.
Blackburn were again without injured top scorer Adam Armstrong with a tendon injury.
They did, however, improve before the break as Rankin-Costello's long-range shot was held at the second attempt by David Stockdale.
Tom Trybull then headed over from Harvey Elliott's corner before Rankin-Costello limped off injured.
Tony Mowbray's side were struggling in the attacking third with Lewis Holtby's mishit effort from Elliott's cross summing up the half.
Young Wycombe midfielder Anis Mehmeti saw his effort deflect wide after a fine piece of skill just after the break.
And from the resulting 47th-minute Jacobson corner, Onyedinma was left unmarked to head past Thomas Kaminski.
It was the fourth goal of the season for the Wycombe forward, who was playing left wing-back, but only his second in the league.
In response Sam Gallagher shot just wide of the post for Blackburn from Joe Rothwell's pass.
Mehmeti continued to cause problems for the Rovers defence and his low shot deflected wide of the post.
Rovers had beaten Wycombe 5-0 in the reverse fixture back in October but were nowhere near as clinical this time around.
Mowbray would have been confident of a push towards promotion at that stage, but their chances are now over and this was a lacklustre display overall which had very much an end-of-season feel.
Mehmeti saw an effort cleared off the line by Barry Douglas, and Taylor Harwood-Bellis was unable to convert a Gallagher corner for Blackburn at the other end.
Mowbray's side went so close to an equaliser two minutes from time as Rothwell's superb run and shot was kept out by Stockdale at point-blank range.
But a rare win will delight Wycombe boss Gareth Ainsworth, a former Blackburn season ticket-holder.
