Sussex were facing a serious test of character at Hove today after the sort of batting collapse their supporters thought belonged to the dim and distant.

The third day against Northamptonshire should have been all about skipper Chris Adams after he became only the third player to complete a full set of hundreds against all 18 first-class counties.

But while Adams was pulling off his pads after making the fourth double-hundred of his career, his team-mates were scrambling around finding theirs as Sussex's last six wickets fell for 24 runs in 9.1 overs.

Bowled out for 406, Sussex followed on 164 behind, but openers Ian Ward and Richard Montgomerie negotiated nine overs before the close to reach 31-0. They still trail by 133.

Sussex should be able to get through the last day on a pitch which is still easy paced, but a game that looked destined to end in a sleepy draw at 5pm yesterday might still produce a positive outcome. Unfortunately, it won't be in Sussex's favour.

Adams fell to the first ball after he reached 200 when a clip off his toes went straight to square leg. It was the cue for a good number of spectators to head for the exits. Quite what their reaction was when they got home and checked the score is anyone's guess.

Matt Prior may have been a shade unlucky to fall leg before to his second ball from Ben Phillips which hit him high on the pad. Mark Davis lasted four deliveries before edging Steffan Jones to slip in the next over and Northamptonshire must have sensed the game was swinging their way when Robin Martin-Jenkins lost his off stump aiming an ambitious pull in Phillips' next over.

Martin-Jenkins had batted for 17 overs and helped Adams put on 50 for the fourth wicket. Now Northamptonshire had two new batsmen to attack and they didn't squander their opportunity.

Johann Louw returned to clean up James Kirtley and although Jason Lewry belted three fours to revive Sussex's hopes of avoiding the follow-on, he soon lost his off pole to Louw.

All of which overshadowed an outstanding innings by Adams, the 40th hundred of his career and 19th for Sussex, three of which have come this season.

It wasn't entirely without blemish. Opposing captain David Sales dropped him at slip on 43, he was reprieved by Martin van Jaarsveld, also at slip, on 115 and there was a thick edge when he was 12 short of 200 which would have gone at a comfortable height to second slip had there been one.

His first 50 occupied 141 balls which is slow by Adams' standards, but testament to the accuracy of Northamptonshire's bowling in the first hour. For the second match running he went into a break in the nineties and, bearing in mind the significance of this particular hundred, you can't imagine that he ate much for lunch.

But his 15th boundary, cracked like so many off the back foot through extra cover, took him to his hundred, the second 50 of which was made off just 58 balls. Now he really began to enjoy himself, driving with authority, punishing any width and coming down the pitch to drive off-spinner Jason Brown to distraction.

For most of the morning it looked as if Richard Montgomerie would make a big score as well. The second wicket pair put on 152 in 59 overs with 78 of them scored in 18 overs before Montgomerie played across a straight one from Jones for a season's best 82.

Tim Ambrose contributed only 30 to a fourth wicket stand of 115, but after a run of low scores , he will have benefitted from two hours at the crease. His confidence seemed to be returning when he got under a sweep to give Usman Afzaal an unexpected wicket.

There was no disguising Adams' joy when a square cut off Phillips took him to 200, made off 329 balls in six-and-a-quarter hours. The ball hadn't even reached the boundary, but he'd already taken off his helmet and was triumphantly raising his bat aloft. At that point he can't have imagined that he might need to show the same sort of resolve today to ensure Sussex stave off defeat.