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For those who were watching the 9th inning of the Rays/ChiSox game, can someone tell me how the Jermaine Dye soft line drive to Jason Bartlett, which Bartlett dropped, but still had plenty of time to throw Dye out at first base, but he threw high and drew Carlos Pena off the bag, although Pena was still able to tag Dye before he touched first, even though the ump missed it and called Dye safe...

Can someone tell me how that was called a single, rather than an error on Bartlett?