Chris Adams admits he is worried about the workload facing his two main bowlers Mushtaq Ahmed and Rana Naved.

Ahead of this week's game against Kent, the Pakistan pair have already bowled 64 per cent, or nearly two-thirds, of the overs in Sussex's Championship matches.

There have been extenuating circumstances.

Jason Lewry and Luke Wright have both missed a match because of injury and at Edgbaston last week Robin Martin-Jenkins was unable to bowl after lunch on the first day against Warwickshire after going down with a migraine for the first time in four years.

When Sussex were trying to end Warwickshire's first (and as it turned out only) innings on the second day, Rana bowled 12 overs unchanged and Mushtaq 12.3.

In the first two games Rana has already bowled 76.5 overs and Mushtaq 104.1, a remarkable tally for a slow bowler in April, even one as good as him.

It is hardly surprising that Adams continues to turn to his two best bowlers, of course.

In the 17 Championship matches they have played together since Rana became Sussex's second overseas player in 2005 they have taken 68 per cent of opposition wickets.

Last week's defeat against Warwickshire was only the third Sussex have suffered when Rana and Mushtaq have been in the same side.

But Adams is mindful that the bowling burden has to be shared around a bit more.

The last thing Sussex want is for one, or both, of their champion performers to suffer an injury.

Both have only missed one Championship match through injury since joining the county but if they are over-bowled those exemplary fitness records could be under threat.

Already, Rana has sustained a slight abductor muscle injury and yesterday he picked up a slight stomach strain against Kent. He will definitely rest next week when Sussex play Cardiff UCCE at Hove over three days, starting on Tuesday.

Adams said: "My main concern is the number of overs in Rana and Mushy already.

"I have said before that they are difficult bowlers to get the ball off when they are in rhythm. They are our match-winners and you always call on your best bowlers at important times.

"But I have probably been a bit more relaxed in terms of letting Rana and Mushy bowl when they want to bowl. I am going to have to try and be a bit stricter to try and reduce their workload and not always allow them to carry on bowling searching for those last couple of wickets."

Rana would happily bowl all day for his captain and county but do not expect him to bowl 12-over spells again over the coming weeks.

At Canterbury yesterday it was significant that Adams restricted him to seven overs with the new ball during which he took two wickets.

And Mushtaq, invariably brought into the attack after an hour or so, did not come on until the 30th over.

It helped that Adams had virtually a full-strength bowling attack at his disposal.

Lewry returned after missing the Warwickshire game while Wright hopes to make his comeback next week against the students.

Academy wicketkeeper Ben Brown, who is with the first-team squad at Canterbury this week doing 12th man duties, has been called into an ECB Select squad for their two-day game against Canada between May 17-18.

Brown said: "It's a great opportunity. There are a couple of other keepers in the squad but I'll work hard and see how it goes."