Leeds are likely to be without scrum-half Luke Gale and centre Konrad Hurrell for the rest of the season.
With the Grand Final under eight weeks away, both players will be struggling to play again in 2021.
“It’s not good news from Luke’s scan,” coach Richard Agar said. “It’s a grade three medial so it’s not the scenario he wanted.
“Unfortunately, it’s probably at least six weeks so it’s going to be touch and go for him.
“Konrad has torn his plantar fascia so he’s going to be in a boot for four to six weeks.”
Hurrell’s three-year contract comes to an end this year and he has been linked with a move to St Helens, where he would be reunited with Tonga head coach Kristian Woolf, but Agar says he has been offered a new deal to stay with Leeds.
“You’d probably have to ask Konrad about that,” Agar said. “He’s not told us that he’s signed with St Helens and neither has his agent but that may well be the case.
“We’ve been in dialogue with Konrad about extending his stay and that’s where it is.”
The 30-year-old Hurrell missed the start of the season but has played in all but one of the Rhinos’ last 15 matches.
Last week, the Rhinos confirmed that utility Liam Sutcliffe will also play no further part this season due to a knee injury.
The 26-year-old has been playing through the pain barrier since March but he has finally succumbed to his injury and will undergo surgery this week.
Agar said: “I think he’s played exceptionally well for us given what we’ve known behind the scenes and changes of position whether he’s played full-back, stand-off, centre, right side or left side. I think he’s been a real shining light for us this year.”