The MP4-28 displayed significant speed during winter testing at Jerez de la Frontera, leading to speculation that the car would be an early championship contender. However, it was soon discovered that this speed was a result of a suspension component being incorrectly fitted on Jenson Button's car, which created an extremely low ride height that in turn led to the fast lap times. The team was forced to install the offending part properly as continuing to run the car in such a configuration would prove to be impossible.[17]