Nas wasn't planning on being in the stands when Team USA played for the gold medal in basketball ... he wasn't planning on partying with the guys after the game either ... until Carmelo Anthony and LeBron James talked him into it ... and gave him free courtside tickets.
It's good to have rich friends.
Here's the story -- Nas had been in London to headline a concert and was 6 hours from getting on his return flight back to the States ... when he got a call from his pal Carmelo Anthony.
Nas' rep told us ... the rapper has been friends with 'Melo and 'Bron for a while, and the two made it clear they REALLY wanted Nas to attend the game ... and offered to get him some pretty sick seats if he was down to change his flight.
Nas' rep tells us ... the rapper didn't have to think twice before taking the guys up on their offer ... changing his ticket immediately and extending his hotel room stay because "He didn't want to miss history."
Of course, Team USA CRUSHED Spain in the finals ... and the rapper joined the champions in the gold medal after-party.
Nas' rep tells us, "He's very thankful that Carmelo and LeBron looked out for him ... It was a moment that he will always remember."