Watching Kent bat was like watching paint dry at Canterbury yesterday until South Africa's big-hitter Jason Kemp launched a late violent assault to put Yorkshire in danger of a third consecutive Championship defeat.

Having just scraped a fourth batting bonus point at 400 for seven in 144.4 overs of pure tedium, Kent waited until last man Robbie Joseph joined Kemp with the score on 449 for nine before stepping up the action.

Kemp was 71 at that stage and after striking Darren Lehmann for six he blazed his way to his century by smashing 24 off an over from footsore off-spinner Richard Dawson, whose first ball was worked away for two and the next blocked.

The third delivery was on-driven for six by Kemp, who followed up with a savagely pulled four and then two mightily driven sixes to go to his century off 152 deliveries with seven fours and five sixes.

Dawson was pulled out of the firing line with figures of four for 151 from 43 overs but there was further misery for Yorkshire as Kemp and Joseph dropped down a gear to accumulate runs more steadily and build up a sizeable lead.

They added a frustrating 84 for the tenth wicket before Joseph was out for 29 at 533 in the 178th over to leave Yorkshire trailing on the first innings by 151, Kemp ending unbeaten on 124 from 176 balls with nine fours and five sixes.

Yorkshire had two tricky overs to negotiate to the close and the out-of-touch openers, Matthew Wood and Joe Sayers, were relieved to head back to the pavilion with two runs scored and a lot of work ahead of them today.

Kent resumed the third day on 196 for three and their innings settled into a dreary pattern as Martin van Jaarsveld and Matthew Walker carefully built up a century partnership.

It seemed as if Yorkshire were in for a wicketless morning until striking twice in seven deliveries before the interval, Jaarsveld going for 82 to a bat and pad catch by Joe Sayers off Dawson and newcomer Darren Stevens being lbw to Anthony McGrath.

Kemp came in straight after lunch, when Kent were 307 for five, but there was no immediate attempt to hurry things on, even when Walker cut Dawson straight to Wood at backward point and departed for 60.

Dawson bowled an excellent spell to restrict Kent's advance but the game seemed to be going nowhere as Kemp and Neil Dexter accumulated 81 in 25 overs before Dexter missed an intended drive at Deon Kruis and was bowled to bring the South African his first wicket of the season.

Niall O'Brien was run out when he could not beat Tim Bresnan's throw from the boundary as the batsman attempted a second and there was another wicket for Dawson when Robert Ferley was caught behind.

But that was the signal for the appearance of last-man Joseph and Yorkshire were soon chasing leather as Kemp finally broke loose.