No, it is the other way around xara. The left field is where most balls go because a right-handed batter will always (well 99% of the time) hit towards the left. Try it...pretend you are batting a ball and see where your arms end up pointing (unless you are left-handed, then you will wind up batting right).

The weaker players are put in the right field because fewer balls go there since a much lower percentage of the population is left-handed.

An expression from a sport...
How about 'he is straight as an arrow' (from archery)