Gloucestershire destroyed one of the country's most feared batting line-ups to put themselves in a dominant position on the second day of the CricInfo Championship match against Sussex at Cheltenham.

The second division leaders require a further 201 runs to avoid the follow-on after collapsing to 161-8 in reply to Gloucestershire's 520.

They will have to bat with a great deal more resolve if they are to avert only their second Championship defeat of the season.

Australian one-day international Ian Harvey bowled superbly to return figues of 2-9 from 15 overs, while off spiner Martyn Ball claimed 2-40.

Prolific openers Richard Montgomerie and Murray Goodwin added 52 in 12 overs, only to begin the slide when departing in quick succession before tea.

Montgomerie had plundered 33 runs from 41 deliveries when he attempted to hook James Averis and top-edged to short square leg where Kim Barnett ran in to complete a fine diving catch.

Gloucestershire were delighted when Goodwin followed soon afterwards for 39. Mark Alleyne found the faintest of outside edges and Jack Russell claimed his 950th county dismissal to reduce the visitors to 86-2.

Sussex were under intense pressure when Bas Zuiderent and Michael Yardy fell in the space of two overs shortly after tea with the score on 112.

Ball then had Chris Adams caught at forward short leg, while Umer Rashid hardly helped the Sussex cause when being run out by Dominic Hewson's throw from mid-wicket in pursuit of a foolhardy second run.

Ben Gannon had Matt Prior caught behind and Harvey returned to dismiss Mark Davis and further undermine the leaders.

Jeremy Snape had earlier registered a career-best 131 as Gloucestershire amassed their second highest total of the summer. He faced 189 balls and struck 18 fours and two sixes in surpassing the 119 he scored at Derby in June.

Russell and Ball contributed 32 runs apiece before falling to Adams who finished with 3-131 from ten overs.

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