KEATON JENNINGS' stratospheric rise from the doldrums of last September scaled a magnificent new peak when he dragged Durham back into the contest against Yorkshire yesterday.

His fourth century of the season ruined the champions' hopes of a three-day win at Chester-le-Street. And by the time he had batted for four sessions to score 185 not out he had given Durham the chance of another unlikely win.

It was Jennings' second innings 113 which turned the tables at Edgbaston, but this was an even greater masterclass, carrying Durham to 452 for eight, leading by 301.

His astonishing concentration wore down the depleted Yorkshire attack and allowed Bradford-born Usman Arshad to make a career-best 84 in a seventh-wicket stand of 156.

While vigilance was Jennings' watchword he did not lose sight of any opportunity to cut and drive through the off side.

His first 50, in tricky conditions, was chiselled out over 138 balls, the second came off 90 and the third off 76.

After scoring 12 and 41 at home to Yorkshire last July, Jennings lasted only one more game, making seven and two against Warwickshire, before he was dropped for the last six matches. He was averaging 23.6.

His previous championship best was 127 at Hove in the last match of 2013, but he spent the next two years struggling to nail down a place. Now he's indispensible in all formats.

Arshad played some audacious strokes, launching Adam Lyth down the ground for two big sixes and nonchalantly running Tim Bresnan to third man for his seventh four to reach 50 off 66 balls.

As the stand went past 100, runs began to flow with the same ease as when Bresnan and Jonny Bairstow put on 366, also for the seventh wicket, in last year's fixture.

It was also a reminder of how Riverside pitches can transform as batting had looked very tricky in the first 40 minutes, when Jennings waited until the tenth over to add to his overnight 46.

He had to shrug off an early setback when Michael Richardson was run out for 13.

A ball from Steve Patterson thudded into his pads and ran off towards square leg. Jennings called him for a single, but he hesitated before responding and was well short when Ben Coad's throw hit the stumps.

The only other risk Jennings took was after driving Bresnan's first delivery with the second new ball through extra cover. He just scrambled home for the third run, which took him to his century.

Durham were well ahead by then, but they had been 46 behind on 105 for four, with Patterson and Bresnan offering nothing, when Paul Collingwood strode in to dominate a stand of 117.

His frequent steers to the third man boundary finally persuaded Yorkshire to post a fielder there, although he was fortunate to survive an upper cut off Josh Shaw, which brushed Andy Hodd's gloves. He was on 19 and went on to make 61.

Given the depleted nature of Yorkshire's attack, Bresnan and Patterson had a huge burden to bear and Patterson looked forlorn when an impassioned lbw appeal against Collingwood was turned down.

It wasn't costly as the home captain added only six before the next appeal was upheld, earning a wicket for the re-modelled off spin of Kane Williamson, who was once deemed to have a suspect action.

Ryan Pringle clubbed four fours in his 20 before Bresnan skidded one through to splatter his stumps.

Arshad was missed by Alex Lees at slip on 33, denying Coad a maiden wicket. But it came with the total on 408 when Arshad dabbled outside off stump and edged to Hodd.

There were no late lapses from Jennings as he passed the 177 he made against Durham University at the start of last season. He will have his sights on 200 today and whatever the target for Yorkshire it promises to be an intriguing final day.