Bianca Andreescu's singles stint at the Bett1open did not go as well as she would have liked, as the Canadian fell in the second round to fourth seed Karolina Pliskova. In the doubles category, however, Andreescu has managed to reach as far as the semifinals, partnering with local girl Sabine Lisicki.The pair took on third seeds Asia Muhammad and Ena Shibahara in the quarterfinals on Thursday, which happened to be the same day as the former US Open champion's 22nd birthday.Following the duo's 7-6(4), 1-6, 10-7 upset win over the American-Japanese duo, the tournament organizers surprised the former World No. 4 with a birthday cake. On top of that, the 22-year-old got another happy surprise from the Berlin crowd, who serenaded her with a perfect rendition of "Happy Birthday."Bianca Andreescu Fans@Andreescu_FansThe crowd singing Happy Birthday to @Bandreescu_ after the doubles win🥰1768The crowd singing Happy Birthday to @Bandreescu_ after the doubles win🥰❤️ https://t.co/2TGoBSOsXSGrateful for the double surprise, Bianca Andresscu thanked the fans with a round of applause, as well as her doubles partner. Lisicki also took to Twitter later to wish the Canadian a Happy Birthday, prompting another message of thanks from Andreescu."Happy Birthday Bibi," Lisicki tweeted.Sabine Lisicki@sabinelisickiHappy Birthday Bibi 🥳🥳🥳@Bandreescu_ twitter.com/wta/status/153…wta@WTA🫂 Team SABIBI 🫂 @sabinelisicki & @Bandreescu_ are through to the doubles semifinals in Berlin!#bett1open23912🫂 Team SABIBI 🫂🇩🇪 @sabinelisicki & 🇨🇦 @Bandreescu_ are through to the doubles semifinals in Berlin!#bett1open https://t.co/dWlTUPJc6ZHappy Birthday Bibi 🥳🥳🥳@Bandreescu_ twitter.com/wta/status/153…"Thank you, love," Andreescu responded.Bianca@Bandreescu_Thank you love twitter.com/sabinelisicki/…Sabine Lisicki@sabinelisickiHappy Birthday Bibi 🥳🥳🥳@Bandreescu_ twitter.com/wta/status/153…3298Happy Birthday Bibi 🥳🥳🥳@Bandreescu_ twitter.com/wta/status/153…Thank you love ☺️ twitter.com/sabinelisicki/…Andreescu and Lisicki are slated to take on top seeds Storm Sanders and Katerina Siniakova in the semifinals on Saturday. The winner will take on either the unseeded pairing of Alize Cornet and Jil Teichmann or second seeds Giuliana Olmos and Gabriela Dabrowski in the final.Bianca Andreescu slowly getting into rhythm following her return to actionBianca Andreescu has found her footing rather quickly after her return to action this yearThanks to a pre-planned break from the game for mental health-related reasons, Bianca Andreescu missed the first four months of the 2022 season, playing for the first time only at the Stuttgart Open.The Canadian has since reached the second round at Stuttgart, the third round at the Madrid Open, the quarterfinals at the Italian Open and the second round at the French Open most notably. Along with the most-recent second-round finish at the Bett1open, the former US Open champion has undoubtedly had a better-than-expected return to action.In all five tournaments, the former World No. 4 has ended up losing only to seeded players, and only after giving them a tough fight. The 22-year-old stretched Aryna Sabalenka to three sets in Stuttgart and then did the same to Karolina Pliskova in Berlin.WTA Insider@WTA_insiderBianca Andreescu after defeating Siniakova 64 46 64 in Berlin: "I was playing the right tactics but on grass one point can change the whole match, the set, the game. So I really had to stay focused. She played great tennis, but I'm happy to get through." Faces Pliskova next.23622Bianca Andreescu after defeating Siniakova 64 46 64 in Berlin: "I was playing the right tactics but on grass one point can change the whole match, the set, the game. So I really had to stay focused. She played great tennis, but I'm happy to get through." Faces Pliskova next. https://t.co/kj1G98Od8ZAgainst Iga Swiatek in Rome, Andreescu broke the World No. 1's serve multiple times and almost took the first set before Swiatek managed to fend off the Canadian.Tennis Canada@TennisCanadaBianca Andreescu had 2021 Wimbledon runner-up Karolina Pliskova on the ropes in their second round clash at the #bett1open, but could not quite finish her off. Still, plenty of good signs from Bianca in Berlin. Read more: ow.ly/HXQ550Jy1xp604Bianca Andreescu had 2021 Wimbledon runner-up Karolina Pliskova on the ropes in their second round clash at the #bett1open, but could not quite finish her off. Still, plenty of good signs from Bianca in Berlin. Read more: 👇ow.ly/HXQ550Jy1xpThe former US Open winner will be unseeded at the Wimbledon Championships, meaning that many seeded players will be hoping they do not draw her early on. Grass isn't exactly her strongest surface, as Bianca Andreescu has never gone past the first round at SW19 (two appearances). This year, however, the former World No. 4 will be hoping to change that.