Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Tie no | Home team | Score | Away team | Date |
| --- | --- | --- | --- | --- |
| 1 | Chester City | 1–1 | Sheffield Wednesday | 31 January 1987 |
| Replay | Sheffield Wednesday | 3–1 | Chester City | 4 February 1987 |
| 2 | Watford | 1–0 | Chelsea | 1 February 1987 |
| 3 | Walsall | 1–0 | Birmingham City | 31 January 1987 |
| 4 | Luton Town | 1–1 | Queens Park Rangers | 31 January 1987 |
| Replay | Queens Park Rangers | 2–1 | Luton Town | 4 February 1987 |
| 5 | Swindon Town | 1–2 | Leeds United | 3 February 1987 |
| 6 | Newcastle United | 2–0 | Preston North End | 31 January 1987 |
| 7 | Tottenham Hotspur | 4–0 | Crystal Palace | 31 January 1987 |
| 8 | West Ham United | 4–0 | Sheffield United | 9 February 1987 |
| 9 | Manchester United | 0–1 | Coventry City | 31 January 1987 |
| 10 | Bradford City | 0–1 | Everton | 31 January 1987 |
| 11 | Wimbledon | 4–0 | Portsmouth | 31 January 1987 |
| 12 | Arsenal | 6–1 | Plymouth Argyle | 31 January 1987 |
| 13 | Stoke City | 2–1 | Cardiff City | 31 January 1987 |
| 14 | Aldershot | 1–1 | Barnsley | 31 January 1987 |
| Replay | Barnsley | 3–0 | Aldershot | 3 February 1987 |
| 15 | Wigan Athletic | 1–0 | Norwich City | 31 January 1987 |
| 16 | Swansea City | 0–1 | Hull City | 3 February 1987 |
Question:
Who was the away team on 31 January 1987 when the home team was Wimbledon?
Answer:
Portsmouth