Despite its placement on the secondary arena of Arantxa Sanchez Vicario, one of the Madrid second-round matches on Wednesday was laden with upset potential. Former Roland Garros champion Svetlana Kuznetsova had won 10 of her 13 previous meetings with world No. 3 Agnieszka Radwanska. Kuznetsova also had claimed both of their encounters on clay, including a rout at the 2012 French Open, that showed her superior affinity for the surface. She had rebounded from a dismal start to the season with strong efforts at clay events in Stuttgart and Portugal, whereas Radwanska has produced uneven results this year.

The second game of this battle at the Mutua Madrilena Open showed how little separated the two women. Radwanska finally broke serve on her fifth opportunity in a six-deuce game, claiming the early lead. As she raced out to a double-break advantage, she looked set to avenge her loss to Kuznetsova at Roland Garros two years ago. The world No. 3 soon led by a set and a break as her opponent struggled to protect her serve. 

That was when the plot thickened and wound through a series of twists. The two women combined for just three service holds in the 10 games of the second set, which was not astonishing considering their modest serves and soild returns. Serving second would be a dangerous position in this situation, and so it proved for Radwanska. While she broke Kuznetsova as she served for the set at 5-3, she could not hold serve in the next game as the Russian drew level. Her early momentum evaporated, Radwanska needed to regroup.

Much like Maria Sharapova a day before, the Pole failed to assert herself early in the third set after letting the second set slip away. Like McHale against Sharapova, Kuznetsova charged to a 4-1 lead in the final set as her opponent's serve deserted her. No lead is safe in the Russian's hands, however, despite her two major titles. Kuznetsova had yielded the third set of the Portugal final on Saturday after leading by a double break, and she conceded four straight games as Radwanska earned the chance to serve for the match.

Just as the underdog had failed to serve out the second set, the favorite could not seal victory on her racket in the third. The 16th and final service break of a match that featured 30 break points brought the two women to the brink of a tiebreak. There, Kuznetsova surged ahead again to earn triple match point at 6-3. Tottering on the edge of the precipice, Radwanska showed a fine display of persistence in sweeping the next five points to end their compelling encounter. She had won just four more points and two more service points than Kuznetsova across the previous two hours and 35 minutes, during which each woman had converted eight of 15 break-point opportunities and played 109 points on serve.

That airtight encounter diverged strikingly from the statements delivered by the two top seeds in Madrid.  Looking to reverse an alarming start to the clay season, men's No. 1 Rafael Nadal pounded aging clay specialist Juan Monaco for the loss of just one game. Top-ranked woman Serena Williams showed slightly more mercy against doubles star Peng Shuai, who claimed five games in Serena's 25th straight victory on red clay. 

But Kuznetsova and Radwanska did not produce the only epic of the day in Madrid. Leading American man John Isner fired 23 aces and faced only one break point, which he saved, against lucky loser Marinko Matosevic. Nevertheless, Isner needed three sets, two tiebreaks, and over two and a half hours to fight off the Australian, gifted a spot in the main draw after Novak Djokovic withdrew. Also surprising was the struggle that Grigor Dimitrov encountered against wildcard Marius Copil. Dimitrov had unleashed stirring form to upset Djokovic in the second round of Madrid last year, but this second-round encounter showed less convincing tennis before he closed out Copil in an epic third-set tiebreak.