The talented forward has made just two substitute appearances under Monk since completing a six-match suspension.
Monk has favoured Steven Fletcher and Atdhe Nuhiu in attack as Wednesday have taken 15 points from his eight league matches in charge.
Forestieri has been forced to bide his time on the bench, coming on late in the home double-header with Stoke City and Leeds United.
"They all know the job is to work hard and keep working hard," said Monk. "At this moment in time, he [Forestieri] has missed quite a few games and the team have done very, very well.
"He will get his opportunities, no doubt."
The 29-year-old has endured a stop-start season, featuring only six times. Forestieri has played once from the start in the home defeat to Queens Park Rangers and is still waiting to open his goal-scoring account.
Monk stressed: "We are very happy with Fernando. His attitude has been very good in training.
"He has not played a massive amount of minutes so far but the team have been doing well so he has to earn the right to be in there.
"He is a good player and he is going to be needed. He will get more opportunities like the others for sure.
"I'm sure when he gets more minutes he will keep progressing and do well for us."
It remains to be seen whether Monk will stick with Fletcher and Nuhiu up front when they go to Blackburn Rovers or switch to a 4-3-3 system today. Fletcher, in particular, was a handful in Saturday's goalless draw with Leeds, forcing goalkeeper into a great first half save Kiko Casillas before rattling the woodwork with a fierce shot after the break.
Monk said: "The key is to be adaptable and have a few ways of stamping your authority on a game.
"I felt those two (Fletcher and Nuhiu) in the second half against Leeds gave us the platform to dominate the action in terms of where we needed to be offensively and of course we did well defensively against a good side.
"It is another strength of ours that we can use for certain games and moments in games.
"Knowing that we can deliver that at a high level against a good side like Leeds just gives them more confidence when we face everybody else."
Centre-back Julian Borner is in contention to start after shrugging off an ankle injury but midfielder Massimo Luongo (ankle) is a big doubt.