user: Question: What Playoffs had an Open Cup of 3rd Round?
Columns: ['Year', 'Division', 'League', 'Reg. Season', 'Playoffs', 'Open Cup', 'Avg. Attendance']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'real']
Sample row: [1997.0, 2.0, 'USISL A-League', '1st, Atlantic', 'Division Semifinals', 'Round of 16', 3138.0]
SQL:

assistant: SELECT "Playoffs" FROM "Table" WHERE "Open Cup" = '3rd Round';