The 20-year-old, who will wear the number 30 shirt, made 13 appearances for the Glovers last term.
He has now returned to Huish Park, where the Wales Under-21 international has agreed to remain until late December.
Sheehan has risen through the ranks at the Liberty Stadium, having joined the Premier League club as a trainee in 2005.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Sunderland | 13 | 9 | 2 | 2 | 23 | 9 | 14 | 29 |
| 2 | Leeds UnitedLeeds | 13 | 7 | 5 | 1 | 22 | 8 | 14 | 26 |
| 3 | Sheffield UnitedSheff Utd | 13 | 8 | 3 | 2 | 16 | 6 | 10 | 25 |
| 4 | Burnley | 13 | 6 | 5 | 2 | 17 | 6 | 11 | 23 |
| 5 | Watford | 13 | 7 | 1 | 5 | 22 | 21 | 1 | 22 |
| 6 | West Bromwich AlbionWest Brom | 13 | 5 | 6 | 2 | 14 | 8 | 6 | 21 |
| 7 | Millwall | 13 | 5 | 4 | 4 | 16 | 12 | 4 | 19 |
| 8 | Blackburn RoversBlackburn | 13 | 5 | 4 | 4 | 16 | 14 | 2 | 19 |
| 9 | Bristol City | 13 | 4 | 7 | 2 | 17 | 17 | 0 | 19 |
| 10 | Norwich CityNorwich | 13 | 4 | 6 | 3 | 23 | 18 | 5 | 18 |
| 11 | Middlesbrough | 13 | 5 | 3 | 5 | 14 | 15 | -1 | 18 |
| 12 | Swansea CitySwansea | 13 | 4 | 4 | 5 | 10 | 9 | 1 | 16 |
| 13 | Coventry CityCoventry | 13 | 4 | 3 | 6 | 17 | 17 | 0 | 15 |
| 14 | Derby CountyDerby | 13 | 4 | 3 | 6 | 16 | 17 | -1 | 15 |
| 15 | Hull City | 13 | 3 | 6 | 4 | 15 | 17 | -2 | 15 |
| 16 | Stoke CityStoke | 13 | 4 | 3 | 6 | 15 | 18 | -3 | 15 |
| 17 | Cardiff CityCardiff | 13 | 4 | 3 | 6 | 13 | 19 | -6 | 15 |
| 18 | Sheffield WednesdaySheff Weds | 13 | 4 | 3 | 6 | 15 | 24 | -9 | 15 |
| 19 | Oxford UnitedOxford Utd | 13 | 3 | 5 | 5 | 16 | 17 | -1 | 14 |
| 20 | Preston North EndPreston | 13 | 3 | 5 | 5 | 14 | 20 | -6 | 14 |
| 21 | Luton TownLuton | 13 | 3 | 3 | 7 | 15 | 21 | -6 | 12 |
| 22 | Plymouth ArgylePlymouth | 13 | 3 | 3 | 7 | 13 | 25 | -12 | 12 |
| 23 | Queens Park RangersQPR | 13 | 1 | 7 | 5 | 11 | 19 | -8 | 10 |
| 24 | Portsmouth | 13 | 1 | 6 | 6 | 13 | 26 | -13 | 9 |
| > Championship Full Table | |||||||||
