Both women have enjoyed a relatively easy road to reach the semifinals.
Williams has yet to drop a set and has surrendered just 13 games total. In her last match against poor Carla Suarez Navarro in the quarterfinals, Williams put up double bagels against the Spaniard en route to a victory that took under an hour to finish.
Li has had somewhat of the same road, as she's only dropped one set thus far, but she hasn't been anywhere near as dominant as Williams.
The history between these two women offers more than a clue in regard to who is likely to win. Williams has a commanding 8-2 record against Li with one of those losses coming via walkover when Williams was forced to pull out of the 2012 Rome Masters due to injury.
Li's other victory came in 2008 when she needed three sets to top Williams following a 6-0 loss in the first set. That was Li's lone non-injury victory over Williams and the only one that took place on a hard court.
In fact, Williams and Li have an extensive history on the hard surface, as seven of Williams' eight wins have come on that type of court.
Aside from history determining the outcome, Williams will bring the same overpowering and overwhelming game she has brought with her in every other match this year. Li is a talented player, but Williams brings an extra element to the game that would make anyone except herself intimidated.
Williams' near-perfect tournament leaves little room for Na to make errors and that's something undoubtedly working against Li in this one. It's one thing to play mistake-free tennis against a lesser opponent, but against Williams and her elite skill, it will be an even harder task than normal.
Will Li Na pull off an upset?
However, that's what it will take in order to topple the undisputed favorite on the women's side. While Li has been playing solid tennis throughout the tourney, Williams is playing her best tennis at the moment. Li enters their match after having struggled against Ekaterina Makarova in the quarterfinals.
The writing is on the wall once again that Williams is destined to take home another Grand Slam title and there is nothing that Li nor anyone else can do about it. At this point, the only person who can beat Williams is Williams herself.