I remember being in sports as a kid that age, and HATING the feeling of losing a game! I so didn't want to tell the other team "Good game!" and shake their hands after the game. I'd rather have kicked their shins.
So I think the way she feels is normal.
The trick is, how to channel that feeling into something less angry... Team sports are so tough because even if she plays really well, the team still might lose. For me personally, I ended up deciding that I'd rather participate in individual sports (track, cross country, swimming) than deal with the uncoordinated losers that were always on my teams in softball. (I know, I know, I am a terrible person for thinking it. Not losers, everyone's a winner, blah blah blah... =) Still, for a kid who is a great natural athlete, team sports can be the ultimate in frustration.
My daughter is on an all-star cheer team. Their competitions have judges, and the scoring is pretty subjective. Also, teams with more kids will score higher because they can do a greater number of tumbling passes, etc. So even though my daughter's team was fantastic this year, often times they wouldn't win competitions simply because there were 14 kids on her team, vs. 24 on some other teams. Of course she'd become upset and ask, "Why did we lose?" And I'd just tell her the truth - your team did 28 back handsprings and they did 48. When you get a point for each one... obviously they're going to score higher. In your daughter's case, it's as simple as, the other team ran the bases faster and hit the ball farther. If you want to win 'em all, you'd better hit the batting cage a little harder next week, right? =) Winners are the ones who turn the losses into motivation.
Sports are tough - it's tough to learn to swallow the feeling of losing, but to learn how to manage defeat gracefully AND learn the feeling of excellence, and of the hard work it takes to achieve it, will be priceless later in life.