Saracens lost their place at the top of the English Premiership log with a surprise 22-13 defeat by lowly London Irish.
The Northampton Saints took over as the top club when a 77th-minute try by George Pisi secured a nail-biting 17-16 win over the Exeter Chiefs.
London Irish hit Saracens with a first-half blitz in which they scored three tries, including two in a three-minute period shortly before half-time. And they achieved this with two players in the sin bin at various times during the half.
Saracens may have thought they were on track when Argentinian centre Marcelo Bosch scored in the 13th minute, but that was soon cancelled out and Irish went into the break 22-8 up. Thereafter it was an arm-wrestle until former Bok hooker Schalk Brits scored a consolation try in the 75th minute.
Northampton had to battle all the way, put under pressure by the boot of Gareth Steenson, and they were not helped when former Bulls back row Gerrit-Jan van Velze came on and promptly earned himself a yellow card. They trailed 16-10 until Pisi broke though.
Francois Louw scored a late try which served merely to emphasise Bath's 24-6 win over Newcastle and help make some ground on Saracens and Northampton, but they still trail Northampton by 11 points and Saracens by 10.
Harlequins scored a late try for a 11-10 win over Wasps on Sunday to go into the top four of the log, easing above Leicester, who were given a massive wake-up call by winless Worcester. The champions sneaked home 23-22 on Friday night.
Worcester 22 Leicester 23
Sale 24 Gloucester 19
Bath 24 Newcastle 6
Saracens 13 London Irish 22
Exeter 16 Northampton 17
Harlequins 11 London Wasps 10
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