Martyn, a middle-order batsman, has been drafted in because Stephen Fleming and Yuvraj Singh have international commitments.

Martyn has never before played county cricket, though he did spend the 1991 season on the Leiceste-rshire staff as a 19-year-old to gain experience.

He could make his debut in the National League game against Surrey at Headingley on Sunday.

Martyn has accumulated 2,000 runs in 33 Tests at an average of 46.5.

He was forced to watch on from the dressing room as his team-mates won the 1999 World Cup, but erased those memories by scoring 88 in this year's final against India.

Hopes will be high at Headingley that Martyn can propel Yorkshire to promotion to Division One of the Championship.

The 2001 champions, relegated last season, are sixth on the Division Two ladder, less than 20 points out of the promotion zone with three games to play.

New Zealand captain Fleming was the more successful of Yorkshire's two international players, scoring 392 runs in six championship games and 258 in six National League matches.

Yuvraj, the Indian all-rounder, made less of an impact, averaging just 17 in the championship and 21 in eight NCL games.