Luca Cadalora received his first pole of the season at his home race, sending the Italian press into a frenzy. He would go on to receive seven more poles in his 500 career. Cadalora got lead at the start from Wayne Rainey and John Kocinski. Kevin Schwantz passed Kocinski and closed in 3rd. Rainey rode aggressively and qualified .021 seconds behind Cadalora.

Rainey, in the lead, went through the fast right-hander and got on the gas too early. The back end of his bike went out of control, causing him to lowside. As he slid off the track, the deep furrows in the gravel somersaulted him end-over-end and he landed heavily on his head. He was helicoptered away from circuit with a broken spine.

“I laid there in the sandtrap. The pain I was feeling was ... unbelievable. It felt like there was a hole in the middle of my chest.”

— Wayne Rainey^[2]

Mick Doohan got past Schwantz hoping to catch Cadalora, but was unable to pass him. The Italian fans swarmed the track when Cadalora won.

This was the last race of the former champion Freddie Spencer.

Tad Pilati of the Roberts team said of Rainey:

“There’s no feeling from the center of his chest down. He’s being held at a hospital near Rimini. He’s in stable condition, and the next 48 hours are going to tell us everything.”^[3]

Rainey ended up paralysed from the chest down and would never walk again. However, he stayed in motorcycle racing in management roles and has raced in a hand-control shifter kart, often with his motorcycle racing rival Eddie Lawson. Rainey has raced in the shifter kart exhibition race held at Red Bull United States Grand Prix, which features motorcycle racing legends.

Grand Prix motorcycle racing did not return to Circuito Internazionale Santa Monica until 2007. By then, the circuit had been modified and rerouted clockwise.