Schumacher had already established himself as the driver to beat in German Formula Three by the time the 1990 Macau Grand Prix took place. Racing for Willi Weber's WTS Formula Three team, he won the German F3 Championship that year after a season in which he also competed in the World Sportscar Championship with the Mercedes-Benz junior programme, racing alongside Heinz-Harald Frentzen and Karl Wendlinger.
The Macau Grand Prix — a street circuit race on the Guia Circuit in the Portuguese territory — was the prestige end-of-season event for Formula Three drivers from across the world, and winning it was considered a mark of exceptional ability. Previous winners had gone on to prominent Formula One careers.
The 1990 race featured a two-heat format, with the final result determined by aggregate times. Schumacher placed second in the first heat, finishing approximately three seconds behind Mika Häkkinen of Finland, who was competing in the British Formula Three series.
In the second heat, Schumacher moved ahead of Häkkinen. Under the aggregate scoring format, Häkkinen needed to finish within three seconds of Schumacher to claim the overall victory. In the closing laps, Schumacher made a mistake that allowed Häkkinen to close the gap. As Häkkinen attempted to pass, Schumacher changed his line; Häkkinen followed the move and ran into the rear of Schumacher's car. Häkkinen's race ended in the resulting contact, while Schumacher continued — without a rear wing — to take the chequered flag.
The incident ended Häkkinen's chance of the overall win and was viewed differently by the two men involved. Schumacher was classified as the overall Macau winner. He later gave the prize money from the race to his family, who had debts at the time.
The 1990 Macau Grand Prix was Schumacher's final race in Formula Three before his transition to Formula One. His debut in Formula One came less than a year later, at the 1991 Belgian Grand Prix with Jordan, where he qualified seventh at Spa-Francorchamps — a circuit he had never previously raced — in a car he had tested for only half a day.
The Macau win also established the beginning of a long rivalry with Häkkinen. The two would meet again in Formula One from 1991 onwards, and their championship battles in 1998 and 1999 — which Häkkinen won — became some of the most celebrated in the sport's history. Schumacher himself later described Häkkinen as "the best opponent I've had" and the rival he respected most throughout his career.
The 1990 Macau Grand Prix sits at the intersection of Schumacher's junior career and his Formula One ascent. The same season also produced wins in the World Sportscar Championship with Sauber-Mercedes, broadening his experience beyond Formula Three and accelerating a career trajectory that would eventually yield seven Formula One World Championships.