Rojas is the hottest property in the Australian A League and is now attracting attention from Europe.
According to local media reports, scouts from both clubs will be present at AAMI Park this Saturday to run the rule over Rojas, who will be up against Alessandro Del Piero's Sydney FC.
Should he impress, one or both clubs are expected to place bids of around £500,000 to sign a player many are calling the best in the A-League at the moment.
With the 21-year-old's contract expiring in three months' time, Melbourne coach Ange Postecoglou is resigned to losing the New Zealand international if the right offer came along, but claimed he was unaware of any overseas interest to date.
"I'm in contact with his dad very regularly and at this stage we're confident he'll stay with us until the end of the season," Postecoglou told Herald Sun.
"We've been in constant discussion with Marco and from our point of view we're very happy with his form this season and how he's developing and his development is a priority.
"At this stage we're comfortable with how he's going and where things are at."
The New Zealander, who is of Chilean descent, has scored 10 goals in 15 league matches for Melbourne this term.