Hernandez, who bagged a hat-trick in the victory over Burton Albion last weekend, has been ruled out by a ruptured Achilles meaning Slutsky must reassess his attacking options ahead of Saturday’s trip to Queens Park Rangers.
“Of course it is very difficult when you lose one of the best players on your team for six months and it’s very disappointing,” said Slutsky.
“However, life continues and we have to prepare for our next match with the players that are available to play.
“I went to Abel’s house yesterday to speak with him and he needs special attention now. It’s the type of injury that needs about six months and I think he will be ready around February.”
Slutsky has also lost midfielder Markus Henriksen for up to six weeks because of a foot injury picked up against Wolves in midweek.
“Markus will lose four-to-six weeks. It was a very strong kick to the bone,” added Slutsky.
“We looked at operation or no operation and some doctors have different opinions to others. He will now stop for three weeks and he will hopefully be ready after the international break.”