1983 was the year to compete in a lot of Satellite tournaments. He also made his first steps onto the Professional Men's Tour (Stefan turned pro in 1983). He made a great impression at the Bournemouth tournament where he, as qualifier, made his way into the Semi-Finals where he eventually lost to routinier José Higueras 1-6, 1-6. 

The French Open was about to start and Stefan was to participate in both the Junior- and the Senior tournament. Exit in the Senior tournament unfortunately came in Round 1 of the qualifications. In the Junior-tournament however, he did much better. He reached the Finals and beat Fevrier 2-6, 6-2, 6-1. By then he wouldn't know that this victory would lead to an extraordinary and (until now) unparalleled achievement.

To his success at the French Open, Stefan would add Junior titles from Wimbledon (defeated Boris Becker in Round 1!), the US Open and the Australian Open: he won the Junior Grand Slam in 1983! No tennis player other than Edberg has been able to do this! 

On the Senior tour his exit from Wimbledon came in Round 2: he lost his first 5-set match unfortunately to his fellow countryman Henrik Bergström. At the US Open Aaron Krickstein prevented him from going into Round 2. End station at the Australian Open came also in Round 1. 

On the ATP World Ranking List he made an impressive jump to position 53 to end a successful year.