"You can't play when you're not 100% fit especially at this level"

This quote by Jamie Redknapp is emphasizing the value of remaining in peak physical condition when playing at a high level. He is recommending that if you are not at your best, you will not be able to carry out to the best of your capability. This is specifically true when playing at an expert level, as the competitors is much higher and the stakes are much higher. Redknapp is suggesting that if you are not in leading physical condition, you will not be able to compete with the other players and will not have the ability to perform to the best of your ability. He is stressing the significance of being in peak physical condition in order to achieve success at a high level.