It comes as a huge blow to Rochina after he had started brightly in Sunday's draw with Derby County until the Spaniard sustained a dislocated shoulder just after the half hour.
"It hasn't been very good news for us, or for him," said the Rovers boss.
"He's going to be out for a while, he's got an operation on Wednesday so we'll just see how it goes from there.
"It is his shoulder, it's popped out and he's done it before unfortunately, so we'll just have to see how he goes with the rehabilitation now.
"The lad is gutted, you saw the level of performance that he showed in the first 30 minutes, he was keen to stamp his mark on the game and I'm sure he'll be sat in that hospital bed wondering what he has done to deserve such bad luck.
"I think we are talking months rather than weeks that is for sure, but hopefully with the medical team that we've got then we can reduce the length of time that has been predicted which is roughly around three months maybe longer.
"He's a good lad and he works hard, so I know that with the medical care he'll get after the operation he'll be back as soon as he can."