user: Question: What ground had Portsmouth Reserves as an opponent?
Columns: ['Match', 'Date', 'Competition or tour', 'Ground', 'Opponent', 'Score1']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, '15 September 2008', 'FA Premier Reserve League South', 'A', 'Chelsea Reserves', '0 - 2']
SQL:

assistant: SELECT "Ground" FROM "Table" WHERE "Opponent" = 'Portsmouth Reserves';