Burns broke his jaw during the early stages of his draw with the Mexican boxer, and the Scot has admitted that he thought that his career was over when the pain of the injury failed to subside even after being given morphine.
The 30-year-old told the Daily Record: "I went straight from the ring to the dressing room, and from there to the hospital. When I was lying in my hospital bed in pain, I knew the morphine wasn't kicking in and I started to think that my career was over.
"I could hear Eddie Hearn asking the nurses to give me more morphine and I was lying there wondering how I'd managed to go through 12 rounds with a broken jaw.
"In the ring, I remember saying to myself, 'Just take it one round at a time'. I was watching the girls circle the ring holding up the cards for each round and I was thinking, 'This is the longest night of my life'."
Burns is expected to be fit enough to return to the ring in early 2014, with the Scot targeting a rematch with Beltran in Glasgow.