The experienced batsmen have been axed amid the Redbacks's mediocre period of just three wins from their past 18 Sheffield Shield games.

"We can't just keep rolling along and doing the same things and expect different results," SA's cricket's high performance manager Tim Nielsen told reporters on Friday.

Even by Redbacks standards, the fresh crisis is alarming.

Their winless streak has reached 13 Shield games.

The state last won the Shield in 1995-96. Since then - a period when every other state has won multiple titles - SA have finished last on 10 occasions and are short-odds to make it 11 this season.

SA's brief stretch of near-success when runners-up in consecutive Shield seasons from 2015-16 is a distant memory.

And Ferguson, 34, and Cooper, 32, must shoulder the blame, especially for this winless season, Nielsen said.

"As senior players we just felt the inconsistency in their performance was one of the major reasons," he said.

"It's really us trying to find a way to spark some team performance and probably send a message both to our team and our squad and our supporters."

Ironically, Cooper (517 runs at an average of 34.46) is SA's best-performed Shield batsmen this summer. Ferguson has made 339 runs at 24.21.

Two batsmen who pre-season were touted as Test candidates have floundered: Jake Lehmann averages 36, Jake Weatherald just 29.

SA's bowlers, formidable on paper, have also failed to fire.

Test pace prospects Chadd Sayers (14 wickets) and Daniel Worrall (20 wickets) have played only four Shield games each because of injuries.

Left-arm quick Nick Winter, who shot to prominence last summer with 34 wickets in the last five Shield games, has 19 victims in seven games this season.

Only one-Test paceman Joe Mennie (33 wickets in eight games) has his reputation intact.

Then there's Lloyd Pope: the teen was trumpeted as the nation's most promising spin bowler when, aged 18, he became the youngest bowler to take seven wickets in a Shield innings last October.

He took two more wickets in the next three games and was dropped.

Pope is now struggling after playing for the Sydney Sixers in the Big Bash League.

"He changed a couple of the things he was doing with his action ... he hasn't found it as simple to come back and re-adjust into the four-day way of bowling," Nielsen said.

Australian Associated Press