Despite losing paceman Chadd Sayers to injury, South Australia are on the verge of victory against NSW in the Sheffield Shield match in Adelaide.

The Blues are 7-141 in their second innings at stumps on Wednesday’s second day, a lead of just 58 runs.

But SA will press for a win without Sayers, the Shield’s leading wicket-taker with 38 victims at an average of 18.

Sayers claimed three more NSW wickets on Wednesday before leaving the field with a rib injury, a Redbacks spokesman saying the 25-year-old was unlikely to bowl again in the match.

The injury came as scans on fellow SA quick Kane Richardson revealed a stress reaction in his back which will sideline him indefinitely.

Richardson was injured playing for Australia A against the British Lions two days ago.

The double blows came as SA continued their dominance of NSW, whose batsmen again struggled to combat Sayers (3-19) and Joe Mennie (3-37).

After Sayers took five wickets in the Blues’ first dig and Mennie claimed four, the pair again broke a brittle NSW top order in the second innings.

The Blues were 3-12 before contributions from Peter Nevill (36), Nic Maddinson (28), Brad Haddin (27) and Trent Copeland (25) added some respectability.

Earlier, the Redbacks made 240 and banked innings points, with Jake Brown top-scoring with 64 and Tim Ludeman making 60, in reply to NSW’s paltry first innings of 157.

NSW pacemen Copeland and Doug Bollinger each claimed four wickets but couldn’t prevent SA moving to 20 points on the Shield table – two behind second-placed Queensland and four adrift of competition leaders Victoria.