(BBC) Former Pakistan captain Imran Khan fears fast bowlers “could go the way of dinosaurs” if the international schedule retains its current format.

Imran, 57, said in the annual Cowdrey Lecture at Lord’s that 50-over cricket may have to be axed to prevent “unprecedented” stress on pacemen.

“Maybe we should eliminate 50-over cricket and just have Twenty20 cricket and Test cricket,” he said.

“I don’t believe Test cricket is the same standard as before.”

A campaigning politician and a tireless charity worker, Imran has remained actively involved in cricket as a commentator and pundit since retiring in 1992 after leading Pakistan to World Cup glory.

The first Pakistani to deliver the Cowdrey lecture, Imran was at Lord’s last week to see Pakistan lose the first of their two Tests against Australia, prompting Shahid Afridi to resign the captaincy after just one game in charge.

And he said Afridi was a prime example of a player who could be a brilliant Twenty20 performer, and yet lack the application to be successful at Test cricket.

“The only test of a cricketer is the Test match because his talent and technique is tested. “In Twenty20, if you are very talented you can get away with it, but a good Twenty20 cricketer will not necessarily excel in Test cricket.”

He said having three formats of the game to focus on was particularly demanding for fast bowlers and that during his 1980s heyday things had been different.

He said: “You could rest, or you could have one full over bowling looseners. Now, one-day cricket has put tremendous pressure on bowlers. The amount of stress on a bowler is unprecedented, you don’t have the luxury of loosening up.

“The stress on fast bowlers is incredible. But cricket without fast bowling is never going to be the same standard if a batsman doesn’t test himself against fast bowling.

“I saw [Australia’s] Shaun Tait bowl in the Twenty20s and I thought an alien had come in – you suddenly saw batsmen hopping about.”

The experience of watching him play had reminded Imran of playing against Sylvester Clarke in county cricket. “He terrified batsmen, but couldn’t get into the West Indies team,” he said.

Imran also discussed the standard of umpiring in international cricket, which he felt had improved hugely since neutral umpires were adopted.

“The spirit of game suffered while I was playing. There was a lot of acrimony in the games and when India played against Pakistan it deteriorated to depths you cannot imagine.

“Neutral umpires have changed everything, technology has eliminated so many of the controversies and results are much fairer now. I think it should improve further with the use of [more] technology.”