Shane Monahan scored four tries as Gloucester ran amok in a 47-3 victory over fellow Aviva Premiership side London Irish in the Amlin Challenge Cup.

The six-try romp - Robert Cook and replacement Dan Robson also crossed - sees Gloucester open up a seven point lead in Pool One.

It wasn't all plain sailing for the hosts with Nigel Davies' side still level after 20 minutes, but two Monahan tries and a further two penalties from Freddie Burns saw them go into the break with a clear lead.

Monahan took a great angle after good carrying from Mike Tindall and Sione Kalamafoni, and sprinted home from 30 metres out for the opening try, before the latter then set up the flying winger for number two.

The visitors changed their entire front row at the interval but Gloucester continued to press and full-back Cook crossed on 43 minutes with a solo effort.

Will James was sin-binned for coming in on the wrong side but Irish were unable to capitalise on the extra man and Monahan completed his hat-trick after Charlie Sharples ran the defence ragged.

His fourth try came on 71 minutes and Robson went over two minutes later although Burns - who had been perfect thus far - was unable to convert either score.