Martinez is favourite to land the Reds job after holding talks with the club's owners Fenway Sports Group and the Spaniard is expected to make an announcement about his future on Tuesday.
And should the Wigan boss choose to move to Merseyside, Caldwell insists no-one in the Latics dressing-room would begrudge the decision.
"If the opportunity comes to go to Liverpool, you take it. We all understand that. I'm sure he would take it," Caldwell told the Daily Star on Sunday.
"Roberto Martinez has a great future ahead of him. When you beat Manchester United, Liverpool and Arsenal in the space of a couple of weeks it gets you recognition and hype and he deserves it
"Nothing fazes him. He stays very calm. Having worked with a lot of Scottish and British managers, you see the tea cups being thrown and stuff.
"But he's from Spain and it's a different culture and mentality and he remains very calm. He has what it takes to manage a club such as Liverpool. If that big job comes now then he has to go and show he is good enough.
"Having worked with him and knowing his tactical awareness and the thought he puts into training, then who knows what he could go on and achieve at a big club like Liverpool with their resources? Only time will tell. We all live in the real world and you need an opportunity in life."