The two rivals go into the 2013 season finale with Marquez holding a 13 point advantage over his fellow Spaniard. Both have the chance of winning the title; Marquez his first in his rookie year in the MotoGP class; and Lorenzo his third crown, after claiming the title last year and in 2010.
Here's what needs to happen for Marquez to win the title in his rookie year:
If Marquez finishes fourth or better he will be World Champion, regardless of where Lorenzo finishes, even if he wins the race.
If Lorenzo finishes second, then Marquez needs to finish eighth or better.
If Lorenzo finishes third then Marquez needs to finish 12th or better.
If Lorenzo finishes fourth then Marquez needs to finish 15th or better to become World Champion.
If Lorenzo does not finish in the top four, then Marquez will automatically be World Champion, whatever his own result.
The final round of the 2013 MotoGP World Championship, the Gran Premio Generali de la Comunitat Valenciana, takes place at Valencia this Sunday. More details at www.motogp.com.