A controversial last-gasp penalty by Mikel Arteta handed Everton their first win of the season after Blackburn dramatically missed two spot-kicks.
Tim Howard was Everton's earlier hero when he saved a 46th-minute penalty from Blackburn's Junior Hoilett.
The giant American keeper then watched Mauro Formica's 77th-minute spot-kick slam against the post.
Arteta's late winner came after referee Lee Mason ruled Chris Samba had flattened Marouane Fellaini.
Despite a host of complaints from incensed Blackburn players, the penalty was awarded in the second minute of stoppage time and Arteta's confident finish condemned Steve Kean's men to their third successive league defeat.
Rovers had only themselves to blame, though. They had a chance of opening their Premier League account just after the restart after Everton's inexperienced Ross Barkley brought down Formica for a clear penalty.
Hoilett took careful aim but Howard gambled correctly, dived to his left, and kept the visitors in what was, until that point, a pretty mediocre game.
Blackburn, who dominated the game from a statistical point of view, got a second chance from the spot when Formica was brought down by Phil Jagielka.
But the otherwise impressive Formica could only watch in horror as his penalty hit the foot of the post and bounce away to safety.
Earlier, in a quiet first half, David Dunn hit the woodwork on 10 minutes after lively play from Hoilett.
At the back, Samba made his presence felt after returning from injury. His dominant performance left Everton with few scraps.
Fellaini should have scored for the struggling Merseysiders in the 73rd minute though, but he delayed his shot and sent the ball well over the bar.
Blackburn brought on new signing David Goodwillie who soon had a golden chance to score but the Scot hit the post after being released by Formica.
And Goodwillie, captured from Dundee United this summer, then set up for Formica who brought another world-class save from Howard.
But there was nothing the Everton keeper's opposite number Paul Robinson could do when Arteta broke Blackburn's hearts with virtually the last kick of the game.
Blackburn boss Steve Kean:
"It [the penalty conceded by Samba] was a tough one to take. I thought Chris Samba had got his head on the ball. I couldn't see what was wrong with his header. I've spoken to Chris and he's gutted.
"Don't forget, we hit the woodwork three times and missed two penalties. I know we should always put away penalties but both spot-kick takers showed a lot of bottle in standing up to hit them.
"Losing two of our main players to injury early in the game did not help but we applied ourselves well, looked good in the final third and I was pleased with the opportunities we created."
Everton boss David Moyes:
"I think the two [penalties] Blackburn got were both dives and I think ours was a penalty kick. Then Samba definitely had two hands on Fellaini's shoulders going for the header.
"The game lasts for however long it lasts. You have to take your chances whenever you get them.
"We didn't get an awful lot but when we did, the one penalty kick we got we took it."