Donna Vekic has been in fantastic form at the Berlin Open, with a fair share of the acclaim going to tennis coach Pam Shriver. The former World No. 3, has been working on and off with Croatian star Donna Vekic in 2023, most recently for the tournament in Berlin.Vekic reached the final of the 2023 Berlin Open by beating Maria Sakkari in the semifinals, 6-4, 7-6(8) on Saturday, June 24. It will be her 12th WTA final.During the semifinal, Shriver took to social media to reveal that Vekic has recently called her up for help at the grasscourt tournament."A remote coaching week- Los Angeles to Berlin to help Team Vekic. The 1:45 am wake-up call was worth it and now Donna Vekic vs her friend Maria Sakkari. In tennis you grow up learning it's okay to beat your friend," Shriver wrote on Twitter.Pam Shriver@PHShriver⁦A remote coaching week- Los Angeles to Berlin to help Team Vekic. The 1:45am wake up call was worth it and now ⁦@DonnaVekic⁩ vs her friend ⁦@mariasakkari⁩. In tennis you grow up learning its ok to beat your friend. #grasscourttennis1297⁦A remote coaching week- Los Angeles to Berlin to help Team Vekic. The 1:45am wake up call was worth it and now ⁦@DonnaVekic⁩ vs her friend ⁦@mariasakkari⁩. In tennis you grow up learning its ok to beat your friend. #grasscourttennis https://t.co/QD8OBGrPCbShriver congratulated Vekic after the win, complimenting her Greek opponent as well."What a match between great friends!" Shriver added.Pam Shriver@PHShriverWhat a match between great friends! ⁦@DonnaVekic⁩ ⁦@mariasakkari⁩ 🏼🏼🏼🏼🏼🏼823What a match between great friends! ⁦@DonnaVekic⁩ ⁦@mariasakkari⁩ 👏🏼👏🏼👏🏼👏🏼👏🏼👏🏼 https://t.co/arRt5FuSchDonna Vekic has had some big victories at the 2023 Berlin Open, losing just one set on her way to the finals.In the first round, she defeated Varvara Gracheva, 6-3, 6-2. She then went on to shock Wimbledon champion Elena Rybakina, 6-7(1), 6-3, 6-4, in the second round.Afterward, the Croatian dispatched Elina Avanesyan, 6-2, 7-6(0), with even World No. 8 Maria Sakkari not being able to take a set from her, 6-4, 7-6(8).The final in Berlin, in which she will face either Ekaterina Alexandrova or Petra Kvitova, will be Vekic's second in 2023 at the WTA tour. Previously, she won the Monterrey Open, defeating Caroline Garica, 6-4, 3-6, 7-5.Donna Vekic credits "Panda power" after Berlin Open 2023 semifinal winDonna Vekic at the 2023 Berlin OpenDonna Vekic wasn't among the favorites to win the Berlin Open before the tournament started, but she has fought her way brilliantly all the way to the final.She defeated Varvara Gracheva, Elena Rybakina, Elina Evanesyan, and Maria Sakkari on her way to the final, receiving a special gift after her quarterfinal match.After her win against Evanesyan, a fan approached her from the stands and gave her a mini-Panda toy, which she happily took.Donna Vekic@DonnaVekic twitter.com/thetennislette…The Tennis Letter@TheTennisLetterDid a fan just walk up and hand Donna Vekic a mini Panda after her win?This is too cute 33018Did a fan just walk up and hand Donna Vekic a mini Panda after her win?This is too cute 🐼 https://t.co/ICT8PuCDL4🐼 twitter.com/thetennislette…The 26-year-old had the Panda with her for the semifinals against Sakkari as it was played on the same day. She credited the toy for her win during the post-match on-court interview."I have some Panda power I received from the tournament... Don't worry guys, I still have something in me for tomorrow, so... depends how good my massage is tonight," Vekic said.Besides the massage, Vekic can watch the second semifinals between Ekaterina Alexandrova and Petra Kvitova, while probably wishing for the Russian to win.She has a positive head-to-head with Alexandrova (2-1) and a negative one with Kvitova (1-4). The final will be played on Sunday, June 25.