The centre-half pulled his hamstring against Aston Villa in mid-January and has now aggravated the strain.
This means he is now definitely out of the game against Liverpool on Tuesday, which is being shown live on Sky Sports 2 at 8pm.
Black Cats boss Ricky Sbragia believes the setback could be down to over-training.
He told the Sunderland Echo: "Nyron has aggravated the strain a little bit.
Nothing serious"It's nothing serious but it will delay his comeback for a while.
"We had planned to include him in the reserve game at Wigan Athletic earlier this week. But he felt his hamstring and we withdrew him from the squad.
"It's probably a case of over-training just a little bit, so that is something we are going to have to keep our eye on.
"It's a disappointment for him but it shouldn't set him back too much and thankfully we have got plenty of players for cover in his absence now."
Kenwyne Jones, Steed Malbranque and Teemu Tainio suffered injuries in the goalless draw against Arsenal last time and Sbragia said the club are monitoring their situation.
StrugglingHe said: "Kenwyne Jones was struggling a little bit with his knee at the Arsenal game, which is one of the reasons why he was substituted.
"Steed Malbranque got a slight calf strain and Teemu Tainio also took a knock to the knee but none of those injuries are serious and it's just a case of keeping our eye on them.
"Djibril Cisse was touch and go for the Arsenal game but when it came down to it, he couldn't be risked.
"He's doing straight line running right now and we might bring him back into full training today but, again, we'll have to see how he goes - I know he is desperate to play against Liverpool."