Worcester continued their recent Guinness Premiership revival with a shock 23-19 victory over Leicester at Sixways on Saturday.
The Warriors' win at Sale last week coupled with this success now leaves Leeds Carnegie, who play Bristol on Sunday, staring relegation in the face as the gap at the bottom is stretched to fourteen points.
Once again fly-half Shane Drahm was the Warriors' hero as they took another massive step towards securing top league safety.
The Tigers had the opportunity to temporarily steal top spot from Gloucester and seemed to be on their way after Brett Deacon's first-minute score.
But Australian fly-half Drahm set up Greg Rawlinson late in the first half before engineering second-half tries for wingers Marcel Garvey and Miles Benjamin to seal the win.
Leicester, meanwhile, slip to third in the table but were boosted by scrum-half Harry Ellis' first start in ten months.
Knee ligament damage sustained last May ruled Ellis out of the World Cup but after coming on as a replacement against Leeds last week he managed 56 minutes at the Sixways Stadium.
Samoan winger Alesana Tuilagi also made his first start in a Tigers shirt in three months while 21-year-old flanker Ben Pienaar was making his full debut in the Premiership.
Worcester had Thinus Delport making his 100th Premiership appearance but they could not have made a worse start.
A poor pass by Matt Powell saw Drahm's kick charged down allowing Leicester flanker Deacon to touch down for a simple try. Andy Goode added the extras.
Drahm responded with a well-struck penalty after Leicester hands in the ruck, before reducing the deficit to one point with another successful kick.
On the half-hour mark Goode capitalised on a Warriors offside to stretch the away side's advantage to 10-6.
But Worcester were not done and shortly before the break Drahm fired a long miss-pass out to Rawlinson, who charged through two tacklers to score and put the Warriors a point ahead.
Drahm missed the conversion and in the last play of the half another Goode penalty restored the Tigers' lead.
After their dream start to the first half, the boot was on the other foot for Leicester in the second.
Only three minutes in, a Drahm break created some space for Garvey to scamper over under the posts before the fly-half added the extras.
More Drahm brilliance set up Worcester's third try as the stand-off burst from inside his own half, leaving defenders in his wake, before chipping ahead.
Centre Dale Rasmussen recycled the ball to wing Benjamin, who crashed over and sent the Warriors fans into raptures.
A missed conversion meant their lead was still only ten points and two Goode penalties set up a thrilling finale.
Warriors replacement Drew Hickey was yellow carded with two minutes remaining but despite being camped inside the home 22, the Tigers were left frustrated.
Tries: Rawlinson, Garvey, Benjamin
Pen: Drahm 2
Tries: B Deacon
Pen: Goode 4
Worcester Warriors: 15 Thinus Delport, 14 Marcel Garvey, 13 Dale Rasmussen, 12 Sam Tuitupou, 11 Miles Benjamin, 10 Shane Drahm, 9 Matt Powell, 8 Kai Horstmann, 7 Pat Sanderson (c), 6 Tom Wood, 5 Craig Gillies, 4 Greg Rawlinson, 3 Tevita Taumoepeau, 2 Aleki Lutui, 1 Tony Windo.
Replacements: 16 Matt Mullan, 17 Shaun Ruwers, 18 Will Bowley, 19 Drew Hickey, 20 Ryan Powell, 21 Joe Carlisle, 22 Chris Pennell.
Leicester Tigers: 15 Sam Vesty, 14 Tom Varndell, 13 Ollie Smith, 12 Tom Youngs, 11 Alesana Tuilagi, 10 Andy Goode, 9 Harry Ellis, 8 Jordan Crane, 7 Ben Pienaar, 6 Brett Deacon, 5 Louis Deacon, 4 Martin Corry (c), 3 Julian White, 2 Mefin Davies, 1 Boris Stankovich.
Replacements: 16 Ben Kayser, 17 Marcos Ayerza, 18 Alex Moreno, 19 Gregor Gillanders, 20 Frank Murphy, 21 Ian Humphreys, 22 Matt Cornwell.
Referee: Chris White
Touch judges: Paul Dix, Ashley Reay
Television match official: Brian Abrahams