The 25-year-old, who has a release clause in the region of £7m, joined Mainz from Real Madrid in 2010.
His performances have not gone unnoticed in Germany, however, with a number of sides believed to be interested in securing his services.
The forward will became Schalke's third signing of the summer transfer window.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Hamburger SV | 25 | 12 | 9 | 4 | 55 | 32 | 23 | 45 |
| 2 | FC Koln | 25 | 13 | 5 | 7 | 38 | 30 | 8 | 44 |
| 3 | KaiserslauternKaiserslautern | 25 | 12 | 7 | 6 | 43 | 35 | 8 | 43 |
| 4 | Magdeburg | 25 | 11 | 9 | 5 | 53 | 38 | 15 | 42 |
| 5 | SC PaderbornSC Paderborn | 25 | 11 | 9 | 5 | 39 | 29 | 10 | 42 |
| 6 | Elversberg | 25 | 11 | 7 | 7 | 45 | 31 | 14 | 40 |
| 7 | Hannover | 25 | 10 | 9 | 6 | 32 | 25 | 7 | 39 |
| 8 | Nuremberg | 25 | 11 | 5 | 9 | 43 | 39 | 4 | 38 |
| 9 | Fortuna DusseldorfDusseldorf | 25 | 10 | 8 | 7 | 42 | 38 | 4 | 38 |
| 10 | Karlsruher SCKarlsruher | 25 | 10 | 6 | 9 | 44 | 46 | -2 | 36 |
| 11 | Schalke 04Schalke | 25 | 9 | 6 | 10 | 42 | 44 | -2 | 33 |
| 12 | Greuther Furth | 25 | 9 | 6 | 10 | 37 | 45 | -8 | 33 |
| 13 | SV Darmstadt 98Darmstadt | 25 | 8 | 7 | 10 | 44 | 41 | 3 | 31 |
| 14 | Hertha Berlin | 25 | 7 | 5 | 13 | 33 | 42 | -9 | 26 |
| 15 | Preussen Munster | 25 | 5 | 8 | 12 | 26 | 34 | -8 | 23 |
| 16 | Eintracht BraunschweigBraunschweig | 25 | 5 | 8 | 12 | 23 | 44 | -21 | 23 |
| 17 | SSV UlmUlm | 25 | 3 | 10 | 12 | 25 | 32 | -7 | 19 |
| 18 | Jahn RegensburgJahn | 25 | 4 | 4 | 17 | 14 | 53 | -39 | 16 |
| > 2.Bundesliga Full Table | |||||||||
