Sheffield United moved out of the Championship's relegation zone after a tense 3-2 victory at Leicester gave them their third win in six days.
Chris Wilder's side raced into a two-goal lead inside four minutes with goals from ex-Leicester striker Tom Cannon and Jairo Riedewald.
A superb volley from Sydie Peck gave United a 3-0 lead at half-time.
Leicester improved in the second half and pulled one back through Stephy Mavididi before Jordan James set up a thrilling finish with a spectacular long-range strike after 82 minutes.
But they could not complete the comeback and Wilder saw his side win against the club who turned him down as their new manager last summer.
United beat city rivals Sheffield Wednesday last Sunday and followed that up with another 3-0 victory at home to Portsmouth. Another three goals proved good enough to lift them two points clear of the bottom three.
Leicester manager, Marti Cifuentes's position had been looking fragile at half-time, but his players' second-half display deserved credit.
United took just 64 seconds to open the scoring through Cannon, who was sold to them for £10million last January.
Cannon showed Leicester what they were missing as he capitalised on some poor defending for his second goal in three games.
Mavididi gave the ball away and Luke Thomas was beaten by Femi Seriki. The ball fell to Callum O'Hare whose shot was blocked by Harry Winks. Cannon was able to collect the loose ball and score from close range.
United added a second goal after four minutes after maintaining pressure on the Leicester defence.
Harry Burrows' corner was not dealt with by Leicester and the ball fell to O'Hare whose shot was deflected in by Riedewald, with goalkeeper Asmir Begovic unsighted, for the Dutchman's first United goal.
Leicester looked to have steadied the game before United added a third goal after 32 minutes.
Burrows' corner flicked off Riedewald's head and into the path of Peck who scored his second goal in successive games with a spectacular 20-yard volley.
Leicester supporters made it clear their patience with the team was wearing thin, and the scoreline could have been even worse for them in first-half stoppage time when Tyrese Campbell ran on to a cleverly created through ball from O'Hare. But his angled shot was narrowly wide of the far post.
The home side responded well in the second half after failing to get a shot on target before the break.
They pulled a goal back after 53 minutes through Mavididi when he headed in at the far post following a deep cross from Abdul Fatawu which was out of goalkeeper Michael Cooper's reach.
Cifuentes' side searched for a second goal and the home fans were now behind their team.
Leicester scored a second goal when substitute Boubakary Soumare set up James to score with a powerful drive from 25 yards.
But it was Wilder's side who held on for United's first win at Leicester in 18 years.
Leicester's Marti Cifuentes:
"It's a game that was heavily influenced by the first four minutes. It's difficult to swallow when you are 2-0 down after four minutes. I don't think I've ever seen that before.
"There were some encouraging signals in the second half but the bar was never very high. It's very frustrating, very disappointing. The first half is below the standards I want to set for the club.
"But to do it requires a certain level of things that we were definitely missing in the first half.
"Probably I said certain things that will stay in the dressing room but I'm happy with the reaction in the second half.
"I don't believe in blame or excuse culture. We'll look at what we didn't do well and try to improve that."
Sheffield United's Chris Wilder:
"We know if we win games of football, we're going to climb the league. But our approach, attitude and philosophy was not to come here, sit in and counter attack, we went for the jugular.
"We back ourselves to go and cause the opposition problems. We looked dangerous every time.
"When you're 3-0 down, I always felt it was a dangerous game. Especially when Michael made a mistake for their first goal, he has to own that but he's in credit.
"The atmosphere changed and Michael will be a little disappointed for their second goal - although it was a fabulous finish.
"But we are incredibly together and we had to withstand that pressure at the end, it was a test. It was a nervy finish. But the character of the team shone through."
