Pay attention to the scores displayed in the bottom left corner of the screen to see how points accumulate within each game, how games build into sets between the players.
Notice how the players must score four times (points) before winning a game.
After scoring a fourth point at 2:39, Nadal wins another game.
At 3:25, Medvedev secures two more games, pushing the score to 6-4, which allows him to win one set.
Nadal and Medvedev continue to battle out the sets, until Nadal finally defeats Medvedev after winning his 5th set.