Replaced Pitcher

In the Ga. NFHS sectionals this weekend I had a pitcher that was replaced, she pitched her 5 warm-up pitches and she told me that she had lost her contact. We looked but were unable to find it. The coach then wanted to replace her but the opposing coach came out of dugout and said the the pitcher had to pitch to one batter first. I remembered reading in the rule book that this was not the case. I allowed the new pitcher but now I cannot find it in the rule book can anyone help? Hope I was right.