The Silver Fern strained her left calf two weeks ago in the 59-48 loss to the West Coast Fever in Perth. Scanlan missed the 52-50 win against the Northern Mystics in Invercargill a week later and was expected to return to court for Monday's game against the Queensland Fire-birds, but tweaked the leg during training.
The 31-year-old was having a scan last night to determine how much damage had been done, but team physiotherapist Jenny Ferguson was not optimistic about Scanlan's prospects of playing in what is a must-win game for the Steel.
"She is having an ultrasound [yesterday] and it is just something we have to monitor week by week," Ferguson said.
"It doesn't look good for Sheryl to take the court.
"Hopefully, she has Silver Fern [commitments] coming after this, so we've got to get her in the best shape for that, as well."
That might mean Scanlan misses the Steel's final round-robin match against the New South Wales Swifts, in Invercargill on July 4.
Meanwhile, Steel chief executive Julie Paterson was satisfied with ticket sales for the match but hinted the game might not sell out.
"We've still got a good few hundred left," she said.
"Normally we sell very well in the three to five days leading up to the game."
Overall, tickets sales are up on this time last year despite season ticket sales falling from more than 800 to about 500.
