Sussex's Twenty20 rookies do not expect it will take them long to get swept up in the excitement of the competition which has revitalised county cricket.

Overseas player Yasir Arafat and off-spinner Ollie Rayner will have key roles when the fourth summer of Twenty20 starts tonight with Sussex facing Hampshire at Arundel in their south group opener (5.30pm).

Arafat has been working on the slower balls and yorkers which are vital to keep opposition batsmen guessing.

And Rayner believes the hammering he received from Kent's Justin Kemp in the C&G Trophy earlier this month has given him a taste of what to expect when batsmen tee off - and how to adapt.

Ten days after beating Hampshire to secure their place in the C&G Trophy final, Sussex will fancy their chances of making a winning start - especially as the visitors' talismanic captain Shane Warne is sitting out Twenty20 so he can have his injured shoulder checked out in Australia.

A crowd of more than 5,000 is expected and they, like the players, will all be hoping for more batting-friendly conditions than Sunday when Sussex and Gloucestershire failed to pass 100 runs in the C&G Trophy on the same pitch which will be used tonight.

Too much grass had been left on the wicket but as soon as Sunday's game was over the Arundel ground staff had got the mowers out.

Arundel's leafy surrounds are a sharp contrast to Arafat's first experience of Twenty20 in Pakistan, where they have been playing the shortened form of the game for two years.

He said: "It hasn't really caught on as well back home compared to England. What I'm most looking forward to is playing in front of big crowds.

"The other players have been telling me about the numbers who come and watch and that they really get behind the team, clapping every boundary or wicket or every stop in the field. It is going to feel more like playing in a one-day international."

But wherever it is played, the rules are the same for the fast men: Bowl as straight as you can, vary your pace and do not be afraid to bowl the odd bouncer.

Arafat added: "I quickly learned that you are in trouble if you give batsmen any width, especially outside leg stump, because they go for everything,"

"So I've been working on the variation in my bowling - plenty of slower balls, yorkers and the odd bouncer because as a bowler you have to keep the batsmen thinking all the time. We'll see how it goes."

The good news for Rayner is that his nemesis Kemp will not be in the Kent line-up when the teams meet at Hove on Thursday week.

The South African propelled his side to victory in the C&G at Tunbridge Wells with a blistering onslaught when he hit seven sixes in 11 balls, including four off Rayner, all of which sailed out of the ground.

Kemp is back in South Africa but Rayner believes the experience will help him when Twenty20's other big hitters get the young off-spinner in their sights over the next three weeks.

He said: "I thought I could perform in one-day cricket until Kemp smashed me out of the park, it was a pretty massive learning curve for me. I had pretty decent figures until I changed ends that day.

"But it's invaluable experience and nothing could have prepared me better for Twenty20 than that. I thought I wouldn't have to change anything but now I know I do.

"Wherever I put the ball he put it out of the park. I was upset about it at the time and hopefully I will be able to do it to some poor off-spinner trying to break through in a few years time."

Rayner says Sussex's C&G Trophy glory run has infused the squad with the belief that they can make a real impression in the competition this year after rain ruined their chances of reaching the knockout stages in 2005.

He added: "We've got a really strong squad with a good blend of experienced guys like the captain, Murray Goodwin and James Kirtley and the youngsters who will throw themselves about in the field and have no fear."