| Player | Previous Rank |
|---|
| 1. Rafael Nadal (ESP) | 1 |
| Clear-cut best player of 2008. |
| 2. Roger Federer (SUI) | 2 |
| Needs one more major title to equal Pete Sampras. |
| 3. Novak Djokovic (SRB) | 4 |
| Aussie Open and Masters Cup champ. |
| 4. Andy Murray (GBR) | 3 |
| Has helped to create the "Big Four." |
| 5. Nikolay Davydenko (RUS) | 6 |
| Steady customer. |
| 6. Jo-Wilfried Tsonga (FRA) | 7 |
| France's best. |
| 7. Juan Martin del Potro (ARG) | 5 |
| Only 20 years old. |
| 8. Andy Roddick (USA) | 8 |
| Still has the huge serve. |
| 9. David Nalbandian (ARG) | 9 |
| Lost chance to win a Davis Cup title. |
| 10. Gilles Simon (FRA) | NR |
| Beat Nadal, Federer and Djokovic this past season. |
