Mumbai, July 9 -- Aryna Sabalenka sank to her knees, arms waving, complaining to her box as she sent what should have been an easy forehand putaway horribly wide. Over a hundred spots separate top seed Sabalenka and world No.104 Laura Siegemund in the WTA rankings. But on Tuesday, in front of a packed Centre Court at the All England Club, the German hassled, harried, frustrated, annoyed and pushed Sabalenka to the edge. Just when it seemed that Siegemund was poised to pull off the greatest win of her career and give Wimbledon the biggest upset of this edition, Sabalenka clawed her way back to pick up a hard-fought 4-6, 6-2, 6-4 win and make it to a third semi-final at SW19. "That was a real task. She pushed me so much," Sabalenka said, still breathless in her on-court interview after the two-hour, 54-minute match. "Honestly, after the first set, I was looking at my box thinking, 'guys, book the tickets, we're about to leave this beautiful place." "(Siegemund) played an incredible tournament, incredible match, I'm just super happy with the win." Siegemund, at 37 years and 118 days, became the oldest player to reach her first quarter-final at Wimbledon. Along the way she beat 29th seed Leylah Fernandez and world No.8 Madison Keys. And with her playing style, it's not difficult to understand how she managed to score those wins. The seasoned player with great variation does not give her opponents many chances to find rhythm. The groundstrokes are not very powerful, but what is devastating - especially on grass courts - is her slice off both wings. She plays drop shots regularly, pointing to her proficiency as a doubles player. And on her own service games, she takes the entirety of the allotted 25 seconds between points - sometimes even sneaking a few seconds beyond. "I'm pretty consistent with my weirdness," she had said in the press conference after reaching the quarter-final. "I do it for me and not against other ones, but it does lead to confrontation sometimes. Then I'm just, like, well, that's how I am." That playing style took a toll on the big-serving, hard-hitting Sabalenka. Perhaps what might have been even more disruptive to the Belarusian's psyche was the fact that Siegemund would, almost casually, return a big serve with a drop shot winner. Credit to Sabalenka though, she kept her emotions in check long enough to eke out the win. "It's a smart game. She's making everyone work against her," Sabalenka said about her opponent. "Going into the match against her, you know you have to work for every point. It doesn't matter if you are a big server or a big hitter, you'll have to work, you'll have to run and you'll have to earn the win. "I was trying to focus on myself. I didn't want her to see that I was annoyed or anything, even if I was a bit on some points." Sabalenka had to adjust. Towards the end of the match, she started to play more slices than hit heavy groundstrokes....