But that was then sensationally overshadowed by Somerset's Ian Blackwell hitting an unbeaten century off 100 balls. with 11 fours and four sixes.

The burly left-hander was severe on Matthew Hoggard, who was repeatedly hooked and pulled to the boundary as the England paceman deliberately bowled short.

In one over Hoggard was thrashed for two sixes and three fours by Blackwell.

When Hoggard was removed from the attack his second spell had cost him 64 runs in ten overs.

Blackwell charged to his century off the penultimate ball of the day from Richard Dawson, which he slammed high over long on and Somerset closed on 186 for six in reply to Yorkshire's 213.

Silverwood's fluent strokes had earlier brought him an unbeaten 44 at a run a ball, with eight boundaries, and he then steamed in at the pavilion end to grab three Somerset wickets with his first 27 balls while conceding only a single.

Although 16 wickets fell yesterday - five of them to England's Andy Caddick - there were no complaints at all from pitch liaison officer Peter Walker, who saw every one of them fall.

"The wickets went down to high quality swing bowling from both sides and you have only to look at the way runs were scored to see that there was nothing wrong with the pitch," said the former Glamorgan and England player.

"Nobody got a ball that bounced awkwardly or shot through and there was hardly a mark on the above average pitch. The wickets have fallen to quality English bowling."

Not all of the Yorkshire batting was of a high quality, however, and Caddick's haul of 72 for five was the third consecutive innings in which he has taken five wickets against Yorkshire.

In warming up for next week's Test match against Sri Lanka at Lord's, Caddick quickly denied his England team-mate Michael Vaughan the time he wanted in the middle by having him caught at second slip by Keith Dutch and then he delivered a fine ball which trapped Darren Lehmann lbw.

Yorkshire were 146 for seven when Silverwood came in and they would have been deeper trouble without Lumb's bright batting.

With shots to all parts of the ground he made 66 off 95 balls, with nine fours before slicing Caddick to be caught in the slips.

Well that Lumb played, he did not outshine Silverwood who made everything zip off the middle of the bat with tremendous power and his off-drive against Caddick was the shot of the day.

With Caddick returning to pick up the wicket of last man Hoggard, Silverwood was soon racing in from the pavilion end and creating havoc among the Somerset ranks

In his first over, Marcus Trescothick was caught at head height at third slip by Lehmann and soon afterwards Australian Jamie Cox was beaten for pace and had his off-stump uprooted before Peter Bowler fell lbw.

Gary Fellows came on to have Keith Parsons lbw as Somerset went in to tea on 26 for four and after the interval Hoggard picked up two wickets as the score dipped to 75 for six.

But suddenly Blackwell, ably supported by Keith Dutch, went on the rampage with Hoggard being made to suffer the most for his unintelligent bowling.

Blackwell's unbeaten 104 came out of 160 while he was at the crease and his unbroken stand with Dutch was worth 111 in 16 overs.

Updated: 11:43 Thursday, May 09, 2002