The uncontrollable nature of weather has the ability to test the mental toughness of even the strongest players. From a coaching perspective, knowing how to keep your player in the correct mindset, though not to over-coach them, can be a real test.
Having to come off the court during a match can be detrimental to any athlete. We rarely see a player resume at the same maximum level after any sort of delay. When situations like rain delay occur, the most important thing a coach can do is stay calm. As a player exits the court, focus on where they are at physically. Coaches and athletes can take advantage of any type of delay and use it as an opportunity to refuel. Knowing how to be aware of where the player is at physically, and allowing them to recharge but not over rest, is a determining factor for how they begin play after the delay.
As we know, the mental part of the game is just as important as the physical part of the game. When game delays occur, controlling match anxiety is crucial. Help the player find a state of mind that is still engaged and conductive on winning, but will not burn them out and contribute to stress. Players will often feel the stress of both match anxiety and their inability to control outside factors. During this time, think of shifting the players mind to a neutral state, rather than having them shut off their engine completely.
Overall, the best thing a coach can do is stay calm and not over-coach. The pronounced impact on the players physical and mental state during delays can be detrimental to success. As a coach, the main focus should be to keep the player as prepared as possible, but to not push the player to a point of where their physical and mental stress burns them out.