user: Question: Who was the lead when Ritvars Gulbis was the skip?
Columns: ['Nation', 'Skip', 'Third', 'Second', 'Lead']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Belarus', 'Oleksii Voloshenko', 'Siarhei Sarokin', 'Alexandr Radaev', 'Aliaksandr Tsiushkevich']
SQL:

assistant: SELECT "Lead" FROM "Table" WHERE "Skip" = 'Ritvars Gulbis';