If you had been asked before the tournament which two players might stage one of the most entertaining all-court battles of the fortnight, Sara Errani and Agnieszka Radwanska probably wouldn’t have rolled off your tongue. Errani is known as a grinder's grinder, and Radwanska spends much of her time on the retrieving end of rallies. But in their quarterfinal on Tuesday, these two Top 10 players ran each other up, back, and side-to-side for two tight sets and nearly two hours.

In the end, Errani recorded her first win over Radwanska in four tries, 6-4, 7-6 (6), by giving her a taste of her own devilish medicine. The Italian, surprisingly, was the more creative player. She came forward at every opportunity, hitting nearly 40 percent of her shots from inside the baseline. She finished points with the drop shot and drop volley whenever possible; and when Radwanska did track them down, Errani sent her scurrying straight back to the baseline with a lob. Errani finished the match with a more-than-respectable 30 winners against 25 errors, and was 16 of 24 at the net.

But Radwanska is a player who can adjust, and she started to apply more pressure in the second, especially on the Errani second serve—Aga came to the net even more often than Errani, winning 20 of 34 points there. But Radwanska couldn’t build any momentum, couldn’t find an error-less groove. A strong game would be followed by two miscues to start the next one. Errani made her play one more ball, and today Radwanska missed it. Sometimes she was too clever for her own good. Radwanska lost one break point after hitting a drop shot from behind the baseline, and fell behind in the second-set tiebreaker when she tried a jumping backhand in the wind. It’s a customary shot for her, but this time it sailed well wide.

Radwanska made Errani sweat by saving a match point on a 27-shot rally at 5-6 in the tiebreaker. But again, she couldn’t build on it. After the two players switched sides at 6-6, Aga hit a backhand long and a backhand wide to surrender the match—she still has never reached the semis in Paris.

But Errani has, for the second straight year. She also won her first match over a Top 5 player in 29 tries. To do it again, and to make it back to the final at Roland Garros, she’ll have to get past Serena Williams on Thursday. In other words, she'll have to get creative again.