As long as you stay active and maintain proper nutrition you will not lose the results you have gained. Muscle atrophy (strength loss) takes place when activity is dramatically reduced or halted completely, or when improper nutrition forces your body to break down your muscles to use as energy. Because continuing to play your sport will continue to activate your muscles you will maintain your muscle growth. You may use our in-season recommendations and still continue to make steady gains without interfering with your regular training regimen.
Aside from activating muscles and maintaining nutrition, there are no "secrets" to maintaining performance.