user: Question: Who was the runner-up, when the champion was Björn Borg after 1978?
Columns: ['Location', 'Year', 'Champion', 'Runner-up', 'Score']
Types: ['text', 'real', 'text', 'text', 'text']
Sample row: ['Myrtle Beach', 1976.0, 'Ilie Năstase', 'Manuel Orantes', '6–4, 6–3']
SQL:

assistant: SELECT "Runner-up" FROM "Table" WHERE "Champion" = 'Björn Borg' AND "Year" > 1978.0;