by Jessica Martini, Brian DiDonato and Christie DeBernardis LEXINGTON, KY - A $2.2-million colt from the first crop of Horse of the Year American Pharoah garnered top billing during the first session of the Keeneland September Yearling Sale Monday. A total of 138 head changed hands for gross receipts of $48,620,000. The average was $352,319 and median was $260,000. The RNA rate was 34.91%. Last year's super-select Book 1 took place over one day, while this year's Book 1 has been spread out over four days with significantly more horses...