In addition to the racing modes included in the previous Underground game (Circuit, Sprint, Drag and Drift races), four new variations of races have been provided in Underground 2. One racing mode was dropped, this being the Knockout competitions. Still, a Lap Knockout option is available when racing Circuit in non-career races.
A circuit race is a standard race that involves up to four cars driving around a track that loops back to the start line of itself. A circuit race is typically a maximum of four laps and minimum of 2 laps. A sprint race is just like a circuit race except that the track does not loop back to the start line. It's a race from A to B involving a maximum of four vehicles, and because of the track design there is only one lap. Street X races are similar to Circuit races, but they take place on closed courses similar to Drift races.