The former South Africa star hit 12 fours during his 111-ball innings and then dismissed Ian Westwood (30) as the hosts closed on 120 for three in response to 407 for eight declared on a slow pitch.

At stumps, Warwickshire trailed by 287 with seven wickets intact but had struggled to combat fast bowler Johan van der Wath and the nagging accuracy of left-arm spinner Nick Boje.

After rain delayed the start for half an hour, Northamptonshire built purposefully on their overnight 292 for five with Mark Nelson, 21, a product of Stowe School and the England youth system, adding 68 in 17 overs for the seventh wicket.

Left-hander Nelson played his previous first-class match almost a year ago but was assured from the start, glancing the first ball he received from New Zealand star Chris Martin to the boundary.

He was 42 not out at lunch but the interval broke his concentration and Ian Salisbury, 17 years his senior, dismissed him without addition after he had hit five fours and faced only 68 balls.

The declaration at 407 for eight soon followed with Salisbury having taken five for 110 in 33 overs to become the first Warwickshire wrist spinner in 38 years to capture five wickets in a championship innings three times in a season.

Salisbury had returned five for 87 in the previous match against Leicestershire.

Klusener, top of Northamptonshire's batting averages, had made his ninth championship half-century of the summer alongside a hundred against Derbyshire at Chesterfield.

But he a loose drive to a ball pitched outside the off stump from Darren Maddy which flew straight to point proved his undoing.

He began his personal retribution by trapping Westwood leg-before with a low full toss that meant Warwickshire had stumbled from 78 for one - with the dismissal of Navdeep Poonia, caught off the splice in the gully - to 84 for three.

The target of 257 to avoid the follow on seemed distant.

Maddy had been caught at slip off the bowling off Boje from a ricochet and it was left to Jonathan Trott and Jim Troughton, both on nought, to rebuild the innings.

They made a successful start, adding 36 in 18 overs, when bad light ended play, despite spinners Boje and Jason Brown operating together.