It's the match everyone was waiting for when the draw came out, and now it's a reality - two of the biggest legends in women's tennis, the Williams sisters, will square off in the quarterfinals of the US Open. It could be epic - first, get ready for the big match with the above video, which is from their last meeting on hardcourts in the semifinals of the Rogers Cup last summer.
... and now let's get ready for the 27th chapter of their epic rivalry with 10 Things To Know!
(1) Serena Williams (USA #1) vs (23) Venus Williams (USA #23)
Head-To-Head: Serena leads Venus, 15-11
1) Serena doesn't just lead the head-to-head, she leads the Grand Slam head-to-head.
Serena doesn't just lead the head-to-head, 15-11, she leads at Grand Slams, 8-5, including their last three Grand Slam meetings in straight sets (2008 US Open, 2009 Wimbledon, 2015 Wimbledon).
2) But the earlier in the tournament, the better it is for Venus.
In semifinals and finals, Serena leads Venus in the head-to-head, 12-6. But this is a quarterfinal match-up - and in the quarterfinals or earlier, Venus actually leads Serena in the head-to-head, 5-3.
3) And they're 2-2 at the US Open.
It's deadlocked here - Venus won in the 2001 final, Serena won in the 2002 final, Venus won in the fourth round in 2005 and Serena won in the quarters in 2008. All four meetings were straight sets.
4) Serena has lost only two matches all year. All year.
Serena is an incredible 52-2 this year, the only two blemishes in that record coming to Petra Kvitova (in the semifinals of Madrid) and WTA Rising Star Belinda Bencic (in the semifinals of Toronto).
5) Venus beat Bencic en route to this match.
Everyone was talking about a potential Serena-Bencic rematch in the quarterfinals, but Venus took the Swiss out, and in straight sets, too. In fact she's won all four of their meetings in straight sets.
6) Serena won their last meeting; Venus won their last hardcourt meeting.
The last time these two played, at Wimbledon in July, Serena beat Venus in straight sets. But in their last hardcourt meeting, Venus beat Serena in Montréal last August (watch highlights above).
7) The overall head-to-head could easily be 13-12 for Serena, not 15-11.
Venus held match point in two of Serena's wins - in the semifinals of Bangalore in 2008 (Serena won, 6-3, 3-6, 7-6(4)) and in the round robin of the WTA Finals in 2009 (Serena won, 5-7, 6-4, 7-6(4)).
Only one pair has played each other more times in Grand Slams than Serena and Venus.
This will be the 14th Grand Slam meeting between the Williams sisters. Only one pair has played each other more times at Grand Slams in the Open Era - Chris Evert and Martina Navratilova (22 times).
9) Whoever wins will be a heavy favorite in the semifinals.
The other quarterfinal in the top half of the draw features a pair of unseeded players - Roberta Vinci and WTA Rising Star Kristina Mladenovic. Neither player has been to a Grand Slam semifinal before.
Also, Vinci is 0-7 against the Williams sisters (0-4 against Serena and 0-3 against Venus) while Mladenovic, should she advance, will be playing against one of the Williams sisters for the first time.
10) Serena is three wins from history. Can Venus stop her?
This match-up is an absolute blockbuster, but don't forget that Serena is three wins from history - not just the first Calendar Year Grand Slam since Steffi Graf in 1988, but also her 22nd Grand Slam title, which would tie Graf's Open Era record. Nobody's beaten her more times than Venus, though...
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