The 20-year-old, who joined the Baggies last January, will spend an initial 28 days at the League One club.
Allan spent the second half of last season on loan at Portsmouth, but failed to agree a move back to the club this summer.
Allan has been identified as a star of the future.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Sunderland | 14 | 9 | 3 | 2 | 23 | 9 | 14 | 30 |
| 2 | Sheffield UnitedSheff Utd | 14 | 9 | 3 | 2 | 18 | 7 | 11 | 28 |
| 3 | Leeds UnitedLeeds | 14 | 7 | 5 | 2 | 22 | 9 | 13 | 26 |
| 4 | Watford | 15 | 8 | 1 | 6 | 23 | 22 | 1 | 25 |
| 5 | Burnley | 14 | 6 | 6 | 2 | 17 | 6 | 11 | 24 |
| 6 | West Bromwich AlbionWest Brom | 14 | 5 | 7 | 2 | 14 | 8 | 6 | 22 |
| 7 | Millwall | 14 | 6 | 4 | 4 | 17 | 12 | 5 | 22 |
| 8 | Middlesbrough | 14 | 6 | 3 | 5 | 18 | 16 | 2 | 21 |
| 9 | Swansea CitySwansea | 14 | 5 | 4 | 5 | 11 | 9 | 2 | 19 |
| 10 | Blackburn RoversBlackburn | 14 | 5 | 4 | 5 | 16 | 16 | 0 | 19 |
| 11 | Bristol City | 14 | 4 | 7 | 3 | 18 | 19 | -1 | 19 |
| 12 | Norwich CityNorwich | 14 | 4 | 6 | 4 | 23 | 20 | 3 | 18 |
| 13 | Derby CountyDerby | 14 | 5 | 3 | 6 | 18 | 18 | 0 | 18 |
| 14 | Stoke CityStoke | 14 | 5 | 3 | 6 | 17 | 18 | -1 | 18 |
| 15 | Sheffield WednesdaySheff Weds | 14 | 5 | 3 | 6 | 17 | 24 | -7 | 18 |
| 16 | Oxford UnitedOxford Utd | 15 | 4 | 5 | 6 | 17 | 18 | -1 | 17 |
| 17 | Coventry CityCoventry | 14 | 4 | 3 | 7 | 18 | 19 | -1 | 15 |
| 18 | Hull City | 14 | 3 | 6 | 5 | 15 | 18 | -3 | 15 |
| 19 | Luton TownLuton | 14 | 4 | 3 | 7 | 16 | 21 | -5 | 15 |
| 20 | Preston North EndPreston | 14 | 3 | 6 | 5 | 14 | 20 | -6 | 15 |
| 21 | Cardiff CityCardiff | 14 | 4 | 3 | 7 | 13 | 20 | -7 | 15 |
| 22 | Plymouth ArgylePlymouth | 14 | 4 | 3 | 7 | 14 | 25 | -11 | 15 |
| 23 | Queens Park RangersQPR | 14 | 1 | 7 | 6 | 12 | 23 | -11 | 10 |
| 24 | Portsmouth | 14 | 1 | 6 | 7 | 13 | 27 | -14 | 9 |
| > Championship Full Table | |||||||||
