WHILE Durham will be up against two of this season's top wicket-takers over the next four days, the man currently topping their own bowling averages again looks likely to be 12th man.

Rana Naved-ul-Hasan, who has 24 wickets at 15.87, and Mushtaq Ahmed - 22 at 21.59 - have propelled Sussex to the top of division one of the Liverpool Victoria Championship and the Pakistani pair are certain to play at Riverside.

But the presence of Steve Harmison in the Durham line-up could mean that Callum Thorp, who made way for him at Trent Bridge last week, will again be surplus to requirements.

In the season's first three matches Thorp took ten wickets at 21.4 to top Durham's averages ahead of Graham Onions with 20 at 25.2.

It was a big improvement for the Western Australian, who despite being recommended by Mike Hussey looked a strange signing for Durham last season at the age of 30.

He came into the side for the last four games and had figures of none for 208 until Northants got themselves into a tangle trying to set up a target in the final match and handed him three wickets.

Already a late developer, Thorp is certain that he is still improving as a result of the coaching he has received at Durham, although he added: "It takes a while to get used to the conditions, such as the lower bounce and playing in minus three degrees."

At Perth in October, 2002, he took four for 58 for Western Australia in a two-day game against England, recalling that his victims were Rob Key, Mark Butcher, Nasser Hussain and Ashley Giles.

His first-class debut followed and at the age of 27 he then went to the Australian Academy, where most of the others were in their late teens.

"I had played since I was a kid and appeared in junior state sides, but I had a few setbacks with injuries," he said.

"I played half a season for Western Australia and they nominated me for the academy, but I had a back injury at the end of the season and worked more on my batting than my bowling.

"The academy coaches had different ideas and it took me a while to get my head around it and feel the benefit. I always seem to be facing the second new ball when I go in for Durham, but I'd back myself to bat at No 8 if they wanted me to."

Thorp has a British passport because he and his sister are the first two members of their family to be born out of England. His father worked as a printer in London before emigrating, then ran a window cleaning business in Perth for 30 years.

Callum is no longer involved with Western Australia as he would have to be regarded as an overseas player, but he still plays A Grade cricket for Wanneroo, north of Perth, where he first met the Hussey brothers, Mike and David.

In Durham's last home game, against Middlesex, he had the outstanding figures of three for 19 in 15 overs in the first innings and said: "It was nice to do that job for the captain.

"But everyone has bowled well and someone had to miss out at Trent Bridge. Graham Onions has been fantastic. He started well last year but then broke his hand and had some back trouble."

Durham are likely to be unchanged today, while Sussex could bring in James Kirtley for his first championship appearance of the season following the re-modelling of his previously suspect action.

Kirtley has been the most prolific English wicket-taker in the championship in the last five years, although he was upstaged by Naved-ul-Hasan's 54 wickets in nine games last year. The Pakistani is available only for the first two months this season before joining his national squad for their three-Test tour.

The chances of a prompt start today are in doubt following the recent rain and spectators should ring 0870 389 1991 for prospects of play.

Durham (from): D M Benkenstein, J P Maher, J J B Lewis, G J Muchall, G J Pratt, G R Breese, P Mustard, O D Gibson, S J Harmison, G Onions, M L Lewis, C D Thorp.

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