By beating Venus Williams on Monday, Sloane Stephens became the second American to beat both Serena and Venus Williams in a Grand Slam match:
Beat Serena - 2013 Australian Open QF.
Beat Venus - 2015 French Open 1R.
Beat Venus - 1998 Australian QF, 1998 U.S. Open SF, 1999 Australian Open QF, 2004 U.S. Open R16
Beat Serena - 2000 U.S. Open QF.