Fourth-ranked Murray's semi-final against Rafa Nadal was earlier ruled a walkover after the Spaniard pulled out with a knee injury.
There was the air of a virtual walkover in the way Djokovic dealt with a wayward Monaco in the first set.
The Serb, in imposing form, dismissed him in just 27 minutes and took full advantage of the Argentine's numerous unforced errors as he won 24 of 32 points.
"He was incredible, he really played like the world number one and it was tough on me," said Monaco.
But after Djokovic broke to go 3-2 up in the second, Monaco fought back well and forced some errors out of the Australian Open champion, who was finally broken when he served for match at 5-4.
The gritty Argentine took the match into a tie-break - a tight affair featuring several long rallies, including one entertaining 26 stroke exchange won by the Serb.
Monaco, who had been cheered on by a largely Latin-American crowd, went long on the decisive point, however, to hand victory to Djokovic.
"I started very strong, just going for the shots, being very aggressive, then I just wasn't able to close it out," said Djokovic, who is now looking for his third win at Key Biscayne.
"All the credit to him for staying in the match, fighting and coming back (but) I still think I gave him points. I made so many unforced errors that I got him back to the match," he added.
Djokovic has a 7-5 record from previous meetings with Murray although the Scot won the most recent in the semi-final in Dubai three weeks ago and also the last time they met in a final - when Djokovic retired in the second set at Cincinnati.
The pair also met in the 2009 Sony Ericsson final with Murray running out 6-2 7-5 winner and Djokovic knows he can expect a tough encounter in the Florida heat.
"We all know his talent, his potential, and quality," he said of Murray. "He's dangerous on any surface. Obviously here we played finals in 2009 and I lost in straight sets. He likes the conditions. He likes to play in the heat as well, and has a good serve.
"We kind of play similar, as well. We grew up together. We know each other really well and we have been rivals since and good friends off the court. It's going to be a good match.
"I don't think it's going to affect him that much that he hasn't played today, but we'll see what happens," he added.