It's random, but remember that these pitchers are in the same ballpark salary-wise (assuming it's not a random AAA league). If you're talking about an OL (average AAA) then the salary range looks like this for pitchers:
SP 950,000 to 1,849,999
RP 700,000 to 1,499,999
If you have a pitcher with 10 effectiveness, you can bet he won't have many innings. If you have a pitcher with 1 effectiveness, you're likely to get more innings. Both sorts of pitchers can be useful, especially in low cap leagues.
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