Skipper Chris Adams admits Sussex's batsmen need to do their bit to sustain the county's challenge for a second Championship in three years.

Sussex have made their best start since 1937 by winning four of their first five games to open up a nine-point lead at the top of division one.

Tomorrow they face bottom of the table Middlesex at Horsham (10.45).

But they have accumulated just eight batting bonus points - fewer than any of their rivals - and have only scored more than 300 runs on just two occasions in their first innings against Warwickshire and Yorkshire.

Only Matt Prior, Mike Yardy and Murray Goodwin have scored hundreds and they are the only batsmen in the side averaging more than 40.

Sussex's 2003 triumph was not just about Mushtaq Ahmed's 103 wickets. The leg spinner only had the opportunity to attack teams with men around the bat because, more often than not, Sussex could exert scoreboard pressure.

Adams said: "We don't seem to be stacking up the runs as we did in the Championship year.

"It seems the wickets we are playing on are much tougher. The climate during the winter has made it hard work for groundsmen and there are always subtle changes to the ball.

"But the flip side is we are winning games and we didn't get off to this sort of start in 2003. We came with a late flurry and clinched it in the second half of the season."

Sussex supporters will not be complaining as long as Mushtaq and Pakistani compatriot Rana Naved maintain their sensational start. Since Rana's arrival last July the county have won ten Championship matches and lost just two.

The pair have picked up 65 of the 90 wickets taken so far between them with Rana's 33 coming in just four games.

"It has been a two-man show for us so far but that's fantastic," added Adams.

"They get a lot of support from the rest of the team and we are all enjoying our success. Bringing Rana to the club was just the tonic Mushtaq needed to keep him going."

The performances of those two have overshadowed the solid job done by Sussex's other bowlers in the first six weeks of the summer.

Luke Wright and Robin Martin-Jenkins might not have the wickets to show for their efforts but their captain recognises the part they have played in keeping the pressure on opposition batsmen.

Adams said: "They are not having to bowl many overs at the moment but both Luke and Robin are performing very well.

"Then we have James Kirtley on the sidelines itching to have a go and I'm confident Tim Linley could come in and do a job. We are in a very good position at the moment."

Adams predicts another close race for the title. He is concentrating on beating Middlesex but next week's potential top two meeting at Liverpool against Lancashire will already be in his thoughts.

"It will no doubt go down to the wire again," he added. "There are some strong teams all capable of performing well so it looks like it's going to be another great year in the Championship."