are we talking hs, hr high, college? I think it depends on the age group.

basically I would let things sort them out. support your daughter. you can't really fight her battles...teach her to accept her skills and wins graciously .

some athletes get frustrated losing, it's hard. especially if it happens often..but that's part of competing. where is the coach in all of this? if your daughter is a gracious winner and athlete then there is not much she can do. athletics can be difficult for young competitors. sportsmanship isn't taught as it used to be, and that is a shame.