The central midfielder has been absent for a prolonged period of time, with his knee and groin hampering him, but it seems that his return is still some way off.
It is a major blow for Sunderland, who felt he had a chance of making it back for this weekend's match against Burnley, but it seems that he will remain sidelined.
“Lee is getting there slowly,” Poyet said.
“It is a tricky injury because it is the type where if you make a mistake and bring him back too early you will go backwards. We’re making sure everything is spot on.”
Cattermole has become a key player for this Sunderland side, with Poyet managing to draw his very best form out of him.
There has been talk on Wearside of the robust midfielder deserving an England call-up because of his consistent excellence and his return to fitness will be a major boost for a side in need of some positivity.
The fact that he is likely to be out for their match against Burnley could be crucial, however. Without Cattermole, Sunderland seem to lack steel, with none of their other options quite as effective.
It means that their chances of beating the Clarets - as they so badly need to - are slightly impeded, and the likes of Liam Bridcutt and Sebastian Larsson will need to step up and cover for their teammate's absence.