Defeating a champion like Serena Williams is an extraordinary challenge.  Capitalizing on that type of victory looms almost as large, though.  At the Family Circle Cup this week, Jana Cepelova conquered both of those challenges.  

In the second round, the 20-year-old Slovak had stunned the world No. 1 in straight sets.  Most underdogs facing such odds fall in the next round or two, as the record of players who have defeated Serena before a final shows.  Not since the 2009 US Open has any woman won the title after that achievement, and Cepelova is hardly a Kim Clijsters in talent or credentials.  

And yet the world No. 78 knocked off two more seeds in Elena Vesnina and Daniela Hantuchova to reach a surprise semifinal against Belinda Bencic.  A junior No. 1 from Switzerland, the 17-year-old Bencic had vastly exceeded her own expectations in Charleston.  Few knew what to expect between a semifinal featuring a pair of overachievers, and the match came down to the wire in a test of nerves.  After Cepelova won the first set, a second-set lull allowed Bencic to regroup and seize the second set.

Each woman dropped serve only once in the tense final set, which Cepelova threatened to win before the final-set tiebreak arrived.  Neither she nor Bencic ever had contested a final-set tiebreak before, and their edginess showed.  Cepelova fell behind 1-4 at the outset, only for Bencic to hand back the advantage with two ugly double faults.  But the Slovak would need three match points to finish off the Swiss teenager, failing to convert the first match point on her own serve before finally eking out a 9-7 decision.

Although Cepelova will enter her first Premier final as an underdog, she should not lack a chance to win the Family Circle Cup.  Barring her path to the Charleston title is 14th seed Andrea Petkovic, who has not reached a final of this magnitude since 2011.  Petkovic also brings momentum with her after upsetting three top-30 opponents en route to the final.  Her most recent victory came in three sets against Australian Open semifinalist Eugenie Bouchard on Saturday.  

While the stakes always are high in a Premier final, both Charleston finalists will know that they have enjoyed outstanding weeks no matter the result.