The 25-year-old, who joined the Latics from Kilmarnock for a fee of £600,000 in January 2011, failed to score in 25 Premier League matches last season.
According to The Mirror, Rams boss Nigel Clough has been chasing Sammon all summer and the two clubs have now struck a £1.2m deal for the player's transfer.
Sammon's current contract expires in June 2014.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| C | Portsmouth | 45 | 27 | 13 | 5 | 76 | 41 | 35 | 94 |
| 2 | Derby CountyDerby | 45 | 27 | 8 | 10 | 76 | 37 | 39 | 89 |
| 3 | Bolton WanderersBolton | 45 | 25 | 11 | 9 | 83 | 48 | 35 | 86 |
| 4 | Peterborough UnitedPeterborough | 45 | 25 | 8 | 12 | 86 | 58 | 28 | 83 |
| 5 | Barnsley | 45 | 21 | 12 | 12 | 81 | 63 | 18 | 75 |
| 6 | Lincoln CityLincoln | 45 | 20 | 14 | 11 | 65 | 38 | 27 | 74 |
| 7 | Oxford UnitedOxford Utd | 45 | 21 | 11 | 13 | 77 | 55 | 22 | 74 |
| 8 | Blackpool | 45 | 21 | 10 | 14 | 63 | 45 | 18 | 73 |
| 9 | Stevenage | 45 | 18 | 14 | 13 | 55 | 45 | 10 | 68 |
| 10 | Wycombe WanderersWycombe | 45 | 16 | 14 | 15 | 59 | 55 | 4 | 62 |
| 11 | Leyton Orient | 45 | 17 | 11 | 17 | 50 | 54 | -4 | 62 |
| 12 | Exeter CityExeter | 45 | 17 | 10 | 18 | 45 | 59 | -14 | 61 |
| 13 | Wigan AthleticWigan | 45 | 19 | 10 | 16 | 61 | 56 | 5 | 59 |
| 14 | Northampton TownNorthampton | 45 | 17 | 8 | 20 | 56 | 65 | -9 | 59 |
| 15 | Bristol Rovers | 45 | 16 | 9 | 20 | 52 | 66 | -14 | 57 |
| 16 | Charlton AthleticCharlton | 45 | 11 | 20 | 14 | 64 | 64 | 0 | 53 |
| 17 | Reading | 45 | 15 | 11 | 19 | 65 | 68 | -3 | 50 |
| 18 | Shrewsbury TownShrewsbury | 45 | 13 | 9 | 23 | 34 | 64 | -30 | 48 |
| 19 | Cambridge UnitedCambridge | 45 | 12 | 11 | 22 | 39 | 61 | -22 | 47 |
| 20 | Burton Albion | 45 | 12 | 10 | 23 | 39 | 64 | -25 | 46 |
| 21 | Cheltenham TownCheltenham | 45 | 12 | 8 | 25 | 40 | 63 | -23 | 44 |
| R | Fleetwood TownFleetwood | 45 | 9 | 13 | 23 | 46 | 72 | -26 | 40 |
| R | Port Vale | 45 | 10 | 10 | 25 | 41 | 74 | -33 | 40 |
| R | Carlisle UnitedCarlisle | 45 | 7 | 9 | 29 | 41 | 79 | -38 | 30 |
| > League One Full Table | |||||||||
