Rodallega has scored just twice from 11 starts.
But Martinez said: "Good players don't become bad players overnight.
"They go through bad moments of form but they remain capable of doing what they can do. We saw that from Fernando Torres in the Nou Camp and Hugo is very much in that category.
"Hugo is made for the big occasion and he can score you a goal out of nothing. He has the experience of last season and he will be a big asset in the run-in. He's not getting frustrated - it's been quite the opposite. He's been champing at the bit.
"He is a very happy footballer, a real lively character all of the time - and you don't get too many of them. They are a joy to be around and he wants to do what he can to help the team.
"Having him back will be like having a new signing."