Complex sentence: At the WTT Marquee Player Draft on February 16,2017, the Kastles protected Martina Hingis and Venus Williams in the first two rounds and left Mardy Fish unprotected in the second round.
Split into simpler sentences: At the WTT Marquee Player Draft on February 16,2017, the Kastles protected Martina Hingis in the first round. They selected Venus Williams and left Mardy Fish unprotected in the second round.