RickO has the correct thought...take a look at your opponent's roster before you start the series. If a pitcher is tired (not just overused or injured), the robot will NOT start him, but will go to the highest grade starter among those in the rotation who is READY. If none of the other starters qualifies, robot will select the highest-grade reliever who is capable of starting without penalty (those RP's who actually started games in MLB). Then it goes to the highest-grade reliver who is READY. I've been 100% accurate in predicting starting pitchers with this.

As for the "Ace" question, it's my understanding that ROBOT leaves the ace in longer than normal rotation starters, so one of RickO and I are remembering incorrectly. I'm almost sure this question is addressed somewhere on the message board, I just couldn't find it with a quick scan.