I agree with @Frame_Rachel! It's important to stay in control of what you're feeling as best as possible. Maybe add a water break or a snack mid-way before you feel like you lose? The nervous system be affected either by stress or a spike in these mechanisms can contribute to loss of focus, decreased coordination, and reaction time. Other things that can contribute to feelings of this may be related to hydration or nutrition so I'll tag @Heather_C in here for tips! It's all connected, but that's a good things too 🙂
Such a great point, @Leada_M ! @denas , if you're starting to find it hard to concentrate and/or that your energy is waning, it could definitely be helpful to try increasing (or adding) something your pre-game snack, and/or bringing a hydration mix with electrolytes in addition to your water, to stay hydrated while you play!