PLAY was held up for 45 minutes at Riverside yesterday when Sussex's Rana Naved-ul-Hasan suffered what turned out to be a dislocated shoulder. But it proved far more painful for Durham than for the championship leaders.

Durham were sailing along on 233 for two, only 58 behind, but on the resumption they immediately lost Mark Stoneman for 101 and collapsed to 316 all out.

From having every chance of the maximum-points victory which would have nosed them ahead of Sussex, they gained only three of the five batting points and their title hopes nosedived.

Even when Ottis Gibson took two wickets before Sussex had wiped off the arrears of 25, and a third shortly afterwards, the prospect of victory was marred by the knowledge that Durham would still be 1.5 points behind their visitors.

Sussex had advanced to 85 for four when bad light ended play, 60 runs ahead in an intriguing game which could still go either way.

Rana Naved had been bowling at the Lumley End until he was hurt in attempting a sliding stop on the cover boundary.

On the resumption he was replaced by fellow Pakistani Saqlain Mushtaq, who took four wickets in his next seven overs. It started with his sixth ball when the off-spinner bowled left-hander Stoneman round his legs when attempting the sweep shot he had previously played so well.

As the first 20-year-old to score a championship century for Durham since Nicky Peng at Derby in April, 2002, Stoneman had brought ecstasy to Riverside.

But it swiftly turned to agony, albeit not quite so literally as it did for Rana Naved, whose screams of pain brought fears that he might have neck or spinal damage and caused the delay.

It also prompted the first visit in 12 years of an ambulance on to the playing area at the Chester-le-Street ground.

The 29-year-old former Test paceman was placed on a stretcher, which was about to be returned to the small ambulance which is always present at matches when an NHS ambulance arrived.

The players left the field while this was going on and did not resume until 2.30, 15 minutes after the ambulance had departed.

The dislocation of their strike bowler's right shoulder is unlikely to damage Sussex's hopes of a second successive championship as Saqlain and his spin partner, Mushtaq Ahmed, should keep them on top.

Mushtaq bowled the second over yesterday and struck with his sixth ball, although Kyle Coetzer looked unlucky to be adjudged lbw by Mike Harris.

But after earning match figures of ten for 37 at Riverside last season, the leg-spinner was played with relative comfort by Stoneman and Dale Benkenstein and had one for 76 from 22 overs at lunch.

Stoneman, on 55 overnight, was very patient and added only four more boundaries to his previous nine, reaching his century off 215 balls just before lunch.

A single to short third man off Mushtaq took him to the landmark and it was met by rapturous applause from the fans, if not from Sussex, who thought he was caught behind off Robin Martin-Jenkins on 79.

Jason Lewry appeared to have less-than-friendly words with the youngster for pulling a rank long hop to the boundary in the 90s.

Stoneman continued to look unflappable as he added one run in five overs after lunch before Benkenstein drove Mushtaq for the four which brought the injury.

It took the captain to 62, but he added only five more on the resumption before he drove at Mushtaq's googly and got an inside edge into his stumps.

In the next over Phil Mustard drove at Saqlain and the edge was knocked up by one slip and caught by the other.

Two overs later Ottis Gibson also departed for a duck when he skied an attempted big hit off Saqlain to mid-on.

Gordon Muchall needed to build on his solid start, but on 17 he tamely lifted Saqlain straight to deep mid-wicket.

When Mushtaq's top spinner had Liam Plunkett lbw for 14 six wickets had gone down for 50 runs and at 283 for eight a third batting point looked unlikely.

But Paul Wiseman swept impressively and Mark Davies gave a rare glimpse of his ability with the bat in a stand of 32 before both edged Martin-Jenkins to slip.

Gibson continued his remarkable habit of striking in the first over of a spell when his fifth ball swung in to have Chris Nash lbw.

Left-hander Michael Yardy played back and edged to Mustard, then Richard Montgomerie skied a pull to mid-wicket, and with a man injured Sussex were effectively 27 for four.

Murray Goodwin might have been run out in scrambling the single to mid-on which got him off the mark had Mark Davies hit the stumps, but he then set about Graham Onions.

Goodwin was lucky on four when a miscued pull just cleared mid-wicket and Chris Adams, on nine, edged Gibson just over the slips. They had put on 58 when Goodwin fell for 23, edging the deserving Davies low to second slip, where Michael Di Venuto held a good catch. Adams remained unbeaten on 31.