Lewis Hamilton grabbed the pole position for the Mexican Grand Prix on Saturday and Mercedes teammate Nico Rosberg fought back from his rough practice outings to earn the No. 2 spot.
Rosberg's leap into second position came on his final lap after three practice sessions when he struggled to find the pace to stay with his teammate in their duel for the season championship.
The position is critical. Even if Hamilton wins, Rosberg leads by 26 points and can clinch the title by finishing second twice and third in the final three races of the season.
Hamilton has been in top form in chasing him of late. He won the U.S. Grand Prix a week ago to keep his title chances alive, with hopes he can keep pressuring Rosberg into a mistake.
Red Bull's Max Verstappen and Daniel Ricciardo will fill out the second row Sunday at the Autodromo Hermanos Rodriguez.