Wolves' veteran striker Raul Jimenez has been ruled out until January after being learning he needs surgery on his left knee.
The 35-year-old Mexico international has not responded as hoped to treatment for the medial collateral ligament injury he suffered in the EFL Cup defeat at Everton a month ago and will now have an operation later this week.
"Unfortunately Raul's injury has not responded as we expected," said Wolves director of performance Phil Hayward.
"Normally the ligament for a fairly low-grade injury would heal on its own, however this has not responded as we were expecting, and after regularly scanning for the last three weeks, the ligament is not healing in the anticipated way.
"So, he'll have the surgery on Friday in London, and then he'll have around three months of rehabilitation before he's ready to play again. "
There is, however, better news on three other injured Wolves players, Rodrigo Gomes (ankle), Bertrand Traore (hamstring) and Boubacar Traore (calf).
Hayward added: "Rodrigo Gomes is progressing well, but it's still early days. He injured a couple of ligaments in the ankle, so it wasn't a straightforward injury,
"He's still waiting on the inflammation to settle, and then we'll start to build him up and get him back outside as soon as that's settled. It's not going to be a long-term one, so he should be back reasonably quickly.
"Bertrand Traore has had a hamstring issue. It's a fairly small injury, however it is in a particularly problematic part of the muscle, which can commonly recur if we're not careful. So, we have to respect that and take our time with it. But it's not a big injury, he's doing really well, working hard and won't be too long."
"Boubacar Traore has been out for a couple of weeks because of a problem with his calf. He's back on the pitch working with the rehab coaches and doing really well. He's progressing nicely and he'll be back in full training in the next week or two. He's responded really well to the treatment."
Wolves are ninth in the Championship table, outside the play-off places on goal difference only, and will be away to Burnley on Friday evening.