One of the most famous duels is the one between Ayrton Senna and Jean Alesi in Phoenix, 1990.

During the launch, Jean Alesi, who was driving for Tyrrell, managed to go from the 4th place to the 1st, and he remained there until the first half of the race.
Suddenly, Senna caught up with him and the duel started.

Senna managed to overtake him at the end of the big, straight lane, but Alesi accelerated and regained the 1st place.
Being the man he was, Senna did not give up and attacked again in the same place, this time impending on the enthusiastic Frenchman, who still tried to overtake him; thus, the two of them ended up driving side by side upon entering the two following turns.

Finally, Senna won both the duel and the race, with Alesi finishing just 8 seconds later.
This performance made him well sought out by both Williams and Ferrari, who wanted him as a racing driver for the next year.