The Racing Club forward has captured the Nerazzurri's attention after a breakout season in Argentina's Superliga, where he has scored 10 goals in 14 appearances.
Likened to Sergio Aguero by Hernan Crespo, the 20 year-old could win his first international cap this week after receiving a maiden national team call-up from Jorge Sampaoli.
And he is set to get a chance in European football with a switch to Inter expected to be sanctioned after the international break.
"Everything is almost set," Martinez said. "There are some final details to be worked out but when I come back to Argentina there will be a meeting with my agent and everything will be settled.
"I keep repeating though that right now my only thought is about Racing. I want to give 100 per cent for this club and help achieve our objectives.”
Martinez's rapid ascension to Sampaoli's squad could see him win a spot in the World Cup squad.
He will have an opportunity to stake his claim in Argentina's friendlies against Italy in England on Friday and away to Spain.
"Everything happened very quickly. It came as a bit of a surprise [to receive the call-up]," he said. "I worked very hard to get here and I'm happy I get to experience something I have always dreamed about. I can't wait to meet the whole group, not just Lionel Messi."