Pakistan coach Mickey Arthur insists Junaid Khan isn't a serial no-ball offender, despite the paceman's costly blunder in Thursday's ODI loss to Australia.
Australia should have been in all sorts of trouble at 3-46 after debutant batsman Peter Handscomb was caught at slip in the 11th over.
But Handscomb, who was yet to score at the time, earned a reprieve when replays showed Khan had overstepped the mark.
Four overs later, Khan no-balled again in a delivery that saw Handscomb dropped at point.
Handscomb ended up making 82 as Australia cruised to their victory target of 264 with seven wickets and 30 balls to spare.
Arthur said his team can't afford to commit such simple errors if they are to have a legitimate chance of winning the series.
But he was careful not to come down too heavily on Khan.
"He's not such much of a serial offender," Arthur said.
"Junaid was battling into the Fremantle Doctor (breeze) a little bit, so that caused him to over stride.
"But it's still no excuse. We've got to be keeping our foot behind the line."
Pakistan trail 2-1 in the series and must win Sunday's fourth one-dayer at the SCG to keep the five-match series alive.
In a massive boost for the visitors, captain Azhar Ali is set to return after missing two games with a hamstring injury.
"He had a good hit (on Thursday), and ran between wickets with the pads on," Arthur said.
"He had a good field too. We're confident we'll get Azhar back for Sunday.
"It's a massive boost. It gives more solidarity to our top order. I'm looking forward to having him back."
Arthur was confident his team can turn around their deficit, especially if their spinners can weave their magic.
"We go to two grounds now where that suits our attack," Arthur said.
"Sydney has turned all year, and Adelaide is slower too.
"So they are two grounds where our attack definitely comes into play."