She has also been plagued by ankle problems, requiring surgery after the 2011 World Cup in Singapore. Fulcher said Kopua's existing knee problems are unlikely to complicate her recovery.
"Her history of knee issues makes her predisposed to this type of injury but it shouldn't impact on her recovery time," he said.
While their captain is undergoing scans today, the Ferns will be back on the training court as they attempt to pick themselves up for Wednesday night's final test at Waitakere's Trusts Stadium.
Having already meekly surrendered the Constellation Cup with three heavy defeats to the high-flying Diamonds, Kopua's devastating injury turned a difficult series into a disastrous one for the New Zealand side.
Kopua was not available to speak to media yesterday, with the shock and emotion still raw in the camp. The star defender looked distraught as she was carried from the court on Saturday night, leaving her teammates shaken, but Fulcher said Kopua was feeling much brighter yesterday.
"She is in pretty good spirits considering ... she is one tough lady," he said.
Ferns coach Waimarama Taumaunu was pragmatic about the situation her side are now facing. She said the team have no option but to dig deep and work hard to salvage something out of the series.
"We have to deal with injuries all the time, it is part of sport and we just have to pull together and move on.
"It is incredibly disappointing for Casey and the team, particularly when she was playing so well. But I have to say we are very fortunate to have Leana [de Bruin] to slot in at goal keep."
Rookie Silver Fern Kayla Cullen, who is returning from a serious knee injury herself, will replace Kopua in the team for Wednesday's final test and the two-test series against a touring English side later this month.
While Cullen sat out the entire ANZ Championship season after rupturing her anterior cruciate ligament on the eve of the 2013 World Youth Cup, Taumaunu is confident the youngster will be up to international netball.
"She certainly seemed to be on track at [national] trials last month and she has since played, and I understand played very well, in the NPC. It was always my intention to bring her in for the England series, or at the very least she would have got a game with New Zealand A," said Taumaunu.