London Irish end Northampton's unbeaten start to the Aviva Premiership season

Ken Pisi crossed for a consolation try for Northampton

Jonathan Joseph: Provided the spark as Irish routed the league leaders

Jonathan Joseph inspired the biggest upset of the season as London Irish smashed Northampton's unbeaten record with a 39-17 win at the Madejski Stadium.

The England centre scored the Exiles opening try and played a key role in scores from David Paice and Topsy Ojo before Jamie Gibson crossed for the bonus point.

The Saints trailed 33-3 before Ken Pisi and Phil Dowson crossed to make the score respectable but Brian Smith's side were long gone.

A point-less first 24 minutes came to an end when Joseph's grubber kick was moved on by Marlande Yarde before Joseph followed up to score his second try of the campaign.

Irish were unrelenting thereafter, prop Halani Aulika held up short before Steven Shingler extended the lead from the tee.

Joseph hit the line at speed on the Saints' 22 and two phases later Paice was over for the second while an Ian Humphreys 40m drop-goal handed the hosts an 18-0 half-time lead.

Northampton came out strongly after the break but Noah Cato could not find a way through and they were soon hit by a third Irish try - Ojo finishing off after Joseph created an opening from clean lineout ball.

Shingler added another penalty and although Bryn Evans narrowly missed out on a fourth try Irish did not have to wait long before Ofisa Treviranus held off two tacklers to supply Gibson with the bonus score.

Northampton kept plugging away and worked a try for Pisi in the right corner before captain Dowson burrowed his way over.

But Shingler added two further penalties to round off the hosts' best performance of the season and secure a memorable win.

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