Sussex might have to wait another season to end a winless run at Edgbaston which stretches back 21 years.

But thanks to innings of contrasting styles from youngsters Matt Prior and Tim Ambrose their batting unit will be feeling a lot more confident today after a shaky start to the season.

In four previous Championship innings, admittedly all on bowler-friendly pitches, Sussex have scored 239, 204, 279 and 198.

Another total below 300 looked likely when the two 21-year-olds came together with Sussex 235-6 shortly after lunch yesterday and every prospect that they might have to follow on.

By the time they were parted Sussex's position was a lot stronger. They had gained maximum batting points for the first time this season and although they conceded a first innings lead of 55 after being dismissed for 367, Jason Lewry took two wickets with the new ball to reduce Warwickshire to 18-2 second time around.

Their stand of 125 broke a record which had stood since 1932 for Sussex's seventh wicket at Edgbaston and the only disappointment was that neither went on to make the county's first Championship hundred of the season.

Ambrose adopted the cautious approach the situation demanded after Tony Cottey, who had added 29 to his overnight 12 and passed 13,000 first-class runs in the process, gloved a ball down the leg side from Alan Richardson in the 16th over of the day.

He helped nightwatchman James Kirtley take the total to 216 before the dilligent Kirtley drove Ashley Giles to short extra cover for 31. It was Kirtley's first dismissal in five innings and gives him an enviable average of 97.

Robin Martin-Jenkins lost concentration in the over before lunch and was caught behind pushing forward to Dougie Brown and Warwickshire must have sensed this was the opportunity to set up their first Championship win of the season.

Instead the Sussex pair accumulated steadily during the afternoon against an attack which did not carry the same menace it had on day two. Ambrose drove with increasing assurity on both sides of the wicket while Prior's shot selection, particularly when he was tested with some short stuff, was impressive.

He was a shade fortunate when one bouncer from Alan Richardson deflected off his helmet to the third man boundary but when Richardson tempted him again with the next ball Prior deposited it effortlessly over backward square for six.

Ambrose had a 16 overs start on his partner and reached his second fifty of the season when he drove Brown to collect his ninth four in the first over with the new ball. Prior's half-century came off 91 balls, 18 more than Ambrose but after getting there he started to provide the acceleration, overtaking his partner by taking 14 off one over from Richardson with two fours and a second pulled six.

Mel Betts fell to his knees seeking divine inspiration and, fortunately for Warwickshire, his prayers were answered three balls later when the former Durham seamer took three wickets in successive overs after tea as Sussex lost their last four while adding just seven runs.

Prior, who hit a dozen fours and two sixes from 122 balls, was taken at second slip on the drive, Mark Davis caught behind forcing off the back foot and Lewry bowled making room for a heave outside off stump.

Mo Sheikh squared-up Ambrose to finish with 4-60 after he had batted for seven minutes short of four hours, hitting 13 fours.

A decent day for Sussex became a good one when Lewry struck twice in three overs.

First innings centurion Jonathan Trott fell leg before in the second over and then Prior completed a highly satisfactory day with a superb catch to dimiss Tony Frost, diving goalkeeper-style to his left to hang on to an inside edge one-handed.

Mark Wagh and Ian Bell took Warwickshire's advantage to 119 but, like his two team-mates, Martin-Jenkins will be feeling a lot better about himself after trapping Wagh leg before with his first ball. At stumps they were 79-3, a lead of 134.

Warwickshire: 422 all out and 79 for 3. Sussex 367 all out.