Rodallega played for Necaxa previously, racking up 15 goals in 36 matches. He is potentially a replacement for soon to be out of contract Emile Heskey. Strikers Camara could also be leaving as well as the Zaki rumours reported back since November although Steve Bruce is denying the latter.
Lactics boss Steve Bruce said: "He is an exceptional player in South America and will be an exceptional player for us.
"I hope we can tie it up. He is only 23 but he is an exciting player and it would be great if we could get him.
"He's fast, he's big, about 6ft 1in, he's good in the air, rangy rather than thick-set, can score a goal. He's just a genuine all-round striker.
"We're close to it (a deal) but when you're dealing with someone from abroad it is already racked with problems.
"We have to go and apply for a work permit. I believe that has been set for some time next week and I believe that's on the agenda.
"I don't envisage there will be any problems, I hope not anyway."