Pat Cummins stars for NSW in return to shield cricket after 2178 days

Heavy clouds and numerous rain interruptions made for a low-key opening day of action at the SCG as South Australia reached 5-169, but one man smiling was returning NSW fast bowler Pat Cummins.

Cummins bowled with good pace and bounce to take 2-42 off 12 impressive overs, in his first Blues' Shield outing for 2178 days.

A veteran of a single Test in 2011 as a raw 18-year-old, Cummins has missed several seasons after a succession of career-threatening back injuries.

Cummins' six-year Shield wicket drought extended for just four overs into his opening spell, before he had opener Sam Raphael caught at first slip by Trent Copeland for seven as SA slipped to 2-20.

Second-placed SA went into lunch at 3-53, and Cummins doubled his wicket tally with the second ball of his second spell.

This time in-form Jake Lehmann was the victim, caught down the leg side for 24.

"I was really happy with my rhythm," Cummins said.

"Playing a couple of grade and futures games helped me find a tempo that might be different to other formats I have been playing.

"Trying to bowl a bit fuller and get the ball swinging is something you have to put above all else in this format, which is something I really enjoy."

Alongside Cummins, there was another new face in the NSW bowling attack with English leg-spinner Mason Crane on debut - becoming the first import for the Blues since Imran Khan's famed stint during the mid-1980s.

Crane (1-24) got several balls to spin significantly and earned the wicket of Tom Cooper (19), caught trying to loft over the infield.

Copeland impressed alongside Cummins taking 2-61.

Despite the steady fall of wickets, Redbacks No.3 Callum Ferguson played a faultless innings to be 75 not out at the close.

It was a stop-start opening day to a match NSW must win to keep their Shield final hopes alive, with players forced from the field on five occasions.