Ian Harvey proved once again that he is the undisputed king of Twenty-20 cricket by thrashing a sizzling century in Yorkshire's six wicket win over previously unbeaten Derbyshire at Headingley.

The Australian all-rounder has now plundered three of the seven centuries made since the Twenty20 Cup started two years' ago and this latest effort of 109 was the highest of the three.

Harvey said: "It was just another one of those days when nothing went wrong for me. I am feeling pretty good at the crease and the shorter boundaries helped me.

"I am backing myself to hit the ball in certain areas and it paid off. I really have no answer as to why I am so successful in Twenty20 cricket but coming to the crease early always helps."

Yorkshire needed a big innings from someone after Derbyshire had knocked up 195 for eight in front of a 5,585 crowd and Harvey was the man to do it in style.

He charged to his century off only 47 balls and by the time he was bowled by Ant Botha he had slammed nine fours and seven sixes from 55 deliveries.

Even so, Yorkshire had only one over remaining when Michael Lumb cracked the winning boundary to make it two wins out of three and victory over Durham at Headingley tomorrow will give them a good chance of making it to the quarter-finals.

Harvey and Matthew Wood rattled up 30 in three overs before Wood departed, but it was the stand between the Aussie duo of Harvey and Phil Jaques that put Yorkshire in command.

The second wicket pair combined in a Yorkshire record partnership of 124 in only 12 overs, Jaques having contributed a modest 37 with five fours off 30 balls when he was bowled making too much room to cut Botha.

Opening the Yorkshire reply, Harvey began as he intended to go on, picking up Kevin Dean for a big six into the West Stand and following up with two fours as 21 came off the first over.

Mo Sheikh was even more expensive as Harvey helped himself to three fours and two sixes on his way to 50 from 22 deliveries with six fours and three sixes.

Harvey greeted Botha with two more huge sixes in an astonishing piece of batting. It was his second man of the match award in three days because he also scooped it at Trent Bridge on Sunday for his 74 off 32 deliveries.

The most economical bowling for Derbyshire came from former Yorkshire off-spinner Andy Gray, who went for only 27 in his four overs and picked up the wicket of Anthony McGrath.

Bresnan was once again the best of Yorkshire's bowlers with three for 26, getting rid of openers Michael Di Venuto in his first spell and coming back to dismiss Gray.

When McGrath bowled Luke Sutton, Derbyshire were 78 for three in the ninth over but they were pulled round by Jon Moss who clattered a defiant 83.