Geoff Miller believes bridging the gap between domestic and international cricket will be one of the most challenging aspects facing England’s incoming national selector.

Miller was part of the England panel from 2000 to 2013, and was the first man to hold the national selector title for the final five years of his tenure.

Former Middlesex and Kent batsman Ed Smith is expected to be named as James Whitaker’s successor in the role when the England and Wales Cricket Board make a formal announcement in the coming days.

Smith has written of his appreciation of the ‘Moneyball’ approach and is understood to have impressed with his appreciation of data sets, but Miller warned of the unknowns that can muddy the waters.

“Numbers are part of the mix, certainly, but there are other contributing factors for success,” he told Press Association Sport.

“Even with knowledge of the figures you can only be 85-90% certain whether someone is mentally tough enough. There’s ten per cent where you’re not certain how they’ll react (to international cricket).

“You need a knowledge of what is required from international cricket and to understand the gap.

“When we played in the era before central contracts, the top international players were playing county cricket, and the top English players, on a regular basis.

“Top overseas players don’t play as much domestic cricket so at times it’s devoid of the very best players. You need to find out how to measure if players are good enough to step up.”

Miller also laid out the other key qualities the job entailed: dedication, communication and a reliable set of wheels.

“The first necessity of that job is to have the time to do it – six or seven days a week if you’re going to make sure the job is done properly,” he explained.

“Then there’s communication skills. My personal opinion is that every conversation, good or bad, had to be done face to face. We talked to managers, coaches, umpires, respected senior players and we got a feeling for what was going on, on and off the field.

“Then there’s the factor of 60-80,000 miles a year, the driving factor. That’s what it entails.”

Miller was part of the panel when Smith earned three Test caps in 2003, and declined to offer anything further, but wishes him a more substantial stint at the top level as and when he receives the nod.

“If it’s Ed, I wish him good luck,” he said.

“He became part of the side when I was involved but didn’t play an awful lot. But he’s captained county sides, been involved in cricket a long time and commentated.

“My passion is for England to be the top side in the world in all formats and making that happen has to be his duty now.”