Sinclair's weak spot kick was saved by Chiamaka Nnadozie, who dived low to her left in the 50th minute to help Nigeria, the lowest-ranked team in Group B, secure a valuable point at Melbourne Rectangular Stadium.

Bidding to become the first player to score at six World Cups, Sinclair also let a good opportunity slip away in the ninth minute when she fired wide.

"Christine Sinclair scored many, many, many goals for this country and I'm sure the fans, the team and everyone can forgive missing a penalty kick," Priestman told reporters.

"I think penalty kicks are a 50-50 chance and on this day 'Sinc' didn't score.

"Sinc has high standards and is a bit of a perfectionist but at the end of the day, this team and this country love Christine Sinclair more than anything, and so they'll rally around her and we'll be on and have her ready for the next game."

Though Sinclair has scored 190 goals in her brilliant career, she is not usually the Olympic champions' first choice from the spot.

The duty might have gone to Jessie Fleming but the midfielder was ruled out injured.

"It certainly wasn't an in-game choice, it was by design," said Priestman, whose team next face Ireland.

Australia, 1-0 winners over the Irish on Thursday, lead the group on three points, with Nigeria and Canada on one.

Saving Sinclair's penalty gave Nnadozie a measure of revenge. In a 2-2 draw between the sides in April last year, Sinclair scored with a long-range chip after Nnadozie had come off her line.

The 22-year-old said that humiliation was on her mind as she faced down Sinclair on Friday.

"When she took the ball, I was like, OK ... the last time we played against them, she scored (on) me.

"I was very angry. And I told myself this is the opportunity to make things right.

"So it's 1-1 for me and Sinclair."