Chris Gunter was brought down in the area in the 53rd minute by Grant Hanley but was booked for diving, leaving Royals manager Nigel Adkins furious.
Tom Cairney had the best chances for Blackburn, but they have now recorded one win in their last six games following a goalless draw with Reading.
Blackburn made two changes from the defeat at Brighton, with David Dunn and Hanley starting, while Adam Le Fondre and Alex Pearce were the two changes Nigel Adkins made from the draw with QPR.
Rovers had only won once against a side in the top half of the Sky Bet Championship before this game.
But they were inches away from going ahead after 15 minutes when Dunn cut in on the right and saw his left-foot effort deflected onto the post by Kaspars Gorkss before Reading scrambled clear.
Cairney should have scored after 31 minutes when he weaved away from two players into the area but shot tamely at Alex McCarthy with only the goalkeeper to beat.
McCarthy thwarted Cairney again minutes later when Lee Williamson powered into the box and set up the on-loan midfielder, whose side-foot shot took a slight deflection and was heading in but for a terrific fingertip save from the Reading keeper.
In comparison, Reading offered very little but Pavel Pogrebnyak went close after 39 minutes, thundering a header wide from Danny Guthrie's chipped cross wide.
There was real controversy after 52 minutes when Gunter went down under Hanley's sliding challenge. The claim for a penalty appeared a legitimate one, but referee Geoff Eltringham booked the defender for diving, leaving him and his manager seething.
But Blackburn continued to look dangerous in their quest for a second successive home win and King had enough time after 60 minutes to let fly following a lightning break but could not test McCarthy.
Reading have failed to score in only one of their previous five away games and came close when Gunter's low cross found Pogrebnyak but the Russian ballooned over from 15 yards.
As the game wore on, Blackburn remained the team most likely to break the deadlock and Cairney once again tried his luck from a 25-yard free-kick but curled it over the bar.
It was the Royals who should have gone in front after 72 minutes. Guthrie's corner was headed back across goal by Pearce to the unmarked Gorkss, who somehow managed to head over from three yards out.
Ruben Rochina's late appearance off the bench after three months out was a boost to Blackburn but he could not alter the stalemate.