World No. 1 Serena Williams will encounter resurgent Spaniard Carla Suarez Navarro to determine who will advance to the semi-final round of the Mutua Madrid Open. Williams is undefeated in their five previous encounters in the head-to-head series, including a clay court win last season at this very event. Check out the Williams vs Suarez Navarro Head to Head.

In one of the earlier matches on court this Wednesday, Serena Williams outlasted her longtime rival and former world No. 1 Victoria Azarenka to secure her 14th h2h victory over the Belarusian. This was easily one of the more competitive encounters yet, which is a positive sign for Azarenka’s recovery. In the end, however, it was Williams who saved three match points to beat her foe 7-6, 3-6, 7-6(1) in two hours and 43 minutes.

When asked about the former US Open champion, she was quick to compliment Azarenka’s return to form.

“It’s so good to see a Grand Slam champion like her playing so well. I’m always rooting for her when she plays. Yeah, so it’s good to see her on her way back – she’s clearly doing great.”

Williams will now come up against Carla Suarez Navarro, whom she demolished several months ago at the Miami Open final. This time, the Spaniard reached the quarter-final stage with an impressive victory over Ana Ivanovic. She won the encounter 7-5, 1-6, 6-4 in two hours and four minutes of court time, during which, she won 68% of her first service points, saved eight break points and won seven of her won.

This marks the sixth time these two competitors will meet on the professional tour, with Williams leading the series with an impenetrable 5-0 record. While the Spaniard is playing some of the best tennis of her career, it is still difficult to envision her actually toppling the world No. 1 player, who is now on a remarkable 26-match win streak.