The 22-year-old will head to the Liberty Stadium having spent the second half of the 2013-14 campaign on loan at Portsmouth.
The Welshman has failed to secure a regular spot in the Swans first team, but made four senior appearances under former manager Brendan Rodgers.
Alfei made 15 appearances for Portsmouth during his loan stint.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Wycombe WanderersWycombe | 23 | 15 | 5 | 3 | 49 | 25 | 24 | 50 |
| 2 | Birmingham CityBirmingham | 22 | 15 | 5 | 2 | 38 | 17 | 21 | 50 |
| 3 | Wrexham | 24 | 14 | 6 | 4 | 36 | 18 | 18 | 48 |
| 4 | Huddersfield TownHuddersfield | 22 | 13 | 4 | 5 | 36 | 19 | 17 | 43 |
| 5 | Reading | 23 | 12 | 4 | 7 | 39 | 33 | 6 | 40 |
| 6 | Barnsley | 24 | 11 | 6 | 7 | 36 | 33 | 3 | 39 |
| 7 | Stockport CountyStockport | 24 | 10 | 8 | 6 | 36 | 25 | 11 | 38 |
| 8 | Leyton Orient | 23 | 10 | 4 | 9 | 31 | 22 | 9 | 34 |
| 9 | Mansfield TownMansfield | 22 | 10 | 4 | 8 | 29 | 25 | 4 | 34 |
| 10 | Bolton WanderersBolton | 22 | 10 | 4 | 8 | 33 | 33 | 0 | 34 |
| 11 | Charlton AthleticCharlton | 22 | 9 | 6 | 7 | 27 | 21 | 6 | 33 |
| 12 | Lincoln CityLincoln | 24 | 8 | 7 | 9 | 28 | 30 | -2 | 31 |
| 13 | Exeter CityExeter | 23 | 9 | 4 | 10 | 27 | 29 | -2 | 31 |
| 14 | Stevenage | 22 | 8 | 6 | 8 | 18 | 20 | -2 | 30 |
| 15 | Blackpool | 23 | 7 | 8 | 8 | 31 | 34 | -3 | 29 |
| 16 | Wigan AthleticWigan | 22 | 7 | 6 | 9 | 21 | 20 | 1 | 27 |
| 17 | Rotherham UnitedRotherham | 22 | 7 | 6 | 9 | 21 | 23 | -2 | 27 |
| 18 | Peterborough UnitedPeterborough | 23 | 7 | 4 | 12 | 41 | 45 | -4 | 25 |
| 19 | Northampton TownNorthampton | 24 | 5 | 8 | 11 | 23 | 39 | -16 | 23 |
| 20 | Bristol Rovers | 23 | 6 | 4 | 13 | 21 | 38 | -17 | 22 |
| 21 | Crawley TownCrawley | 22 | 5 | 5 | 12 | 24 | 40 | -16 | 20 |
| 22 | Shrewsbury TownShrewsbury | 23 | 4 | 5 | 14 | 24 | 43 | -19 | 17 |
| 23 | Cambridge UnitedCambridge | 23 | 4 | 5 | 14 | 22 | 42 | -20 | 17 |
| 24 | Burton Albion | 23 | 2 | 8 | 13 | 20 | 37 | -17 | 14 |
| > League One Full Table | |||||||||
