Lisicki turned professional in 2006, and her breakthrough came in 2009 when she reached the quarterfinals of the Wimbledon Championships, and also won her first title on the WTA Tour, at the Family Circle Cup.

Lisicki rebounded in 2011 and won the Birmingham Classic, before entering the Wimbledon Championships as a wildcard and going on to reach the semifinals, where she lost to Maria Sharapova.

In doubles, Lisicki won the Porsche Tennis Grand Prix in 2011 with Samantha Stosur and in 2013 with Mona Barthel and the 2014 Miami Open with coach Martina Hingis.

[6] At the Australian Open, her first Grand Slam tournament, she defeated the 16th-seeded player, Dinara Safina, as well as Mariya Koryttseva to reach the third round as a qualifier.

She then took part in Germany's 3–2 win over Switzerland in their Fed Cup World Group II tie, defeating Timea Bacsinszky but losing to Patty Schnyder.

At the Cellular South Cup in Memphis, Lisicki reached the semifinals, defeating third seed Lucie Šafářová on the way before losing to eventual winner Victoria Azarenka.

During the clay-court season, Lisicki lost in the second round of the Amelia Island Championships in Ponte Vedra Beach to eventual finalist and fifth seed Aleksandra Wozniak.

On the green clay at the Charleston Open in, Lisicki won her first WTA Tour title without dropping a set, defeating the fifth seed Caroline Wozniacki in the final.

She returned to the tour at the Pan Pacific Open at the end of September, where she reached the second round before losing in three sets to seventh seed Jelena Janković.

At Wimbledon, she received a wildcard to enter the tournament, advancing to the semifinals of a major for the first time, and beating third seed and recent French Open champion Li Na in the second round.

As a result of the fall in her quarterfinal match, Lisicki was forced to the sideline at the Fed Cup World Group Play-off tie against Australia.

She was also forced to pull out of the Porsche Tennis Grand Prix, from which she was defending a quarterfinal spot in singles and the doubles title which she won with Sam Stosur.

Traveling next to her home country for the Internationaux de Strasbourg, where she was the top seed, Lisicki again experienced a first round upset, losing to Pauline Parmentier.

In mixed doubles, Lisicki and Kas beat second seeds Bob Bryan and Liezel Huber in the first round, and Daniele Bracciali and Roberta Vinci in the quarterfinals.

Lisicki won in three sets, marking the fourth time in her last four participations that she knocked out the reigning French Open champion at Wimbledon.

She then played the Osaka Open, again beating Scheepers in the first round, but was forced to withdraw from the tournament with a left hip injury before her second-round match.

In her first-round match at the Stanford Classic against Ivanovic, Lisicki set a world record serve for a female tennis player, clocked at 210.8 km/h (131.0 mph).

In the quarterfinals, she beat the defending champion Flavia Pennetta in a three set thriller, saving three match points to advance to the semifinals for the first time at a Premier Mandatory event.

Lisicki carried her good form over to Miami where she beat fellow countrywoman Julia Görges, Ana Ivanovic, and Sara Errani to advance to her second Premier Mandatory quarterfinal in a row.

She also played in the doubles with Andrea Petkovic but the pair lost to Pavlyuchenkova and Elena Vesnina to give Russia the win and a place in the final.

Lisicki then played at the Internazionali BNL d'Italia and picked up her first clay win by beating Sloane Stephens before losing to Timea Bacsinszky in straight sets.

Then at the Guangzhou Open, she safely reached the quarterfinals by beating Kwan Yau Ng and Peng Shuai, but finally lost to Jelena Janković.

Lisicki next played at the Hawaii Open and beat Julia Boserup and Verónica Cepede Royg, but retired injured in the third set of her quarterfinal against Jacqueline Cako.

She received a wildcard for the Wimbledon qualifying, where she lost in the final round to Lesley Pattinama Kerkhove, after defeating Tímea Babos and Ankita Raina.

Her first event of the year was the WTA 125 Prague Open, where she reached the fourth round, defeating Samantha Murray Sharan, Stephanie Wagner, and Chihiro Muramatsu, before losing to Francesca Jones.

In doubles, at the same event with Jodie Burrage, she retired from her first-round match against Ulrikke Eikeri and Yana Sizikova, whilst the pair led 6–5 in the first set.

In May, eighteen months after surgery, Lisicki made her return to professional tennis in the qualifying draw of the FineMark Pro Championship, a $100k event played on clay courts.

Lisicki won her first main draw match on the WTA Tour since 2018 as a wildcard at the Bad Homburg Open, defeating her compatriot Tamara Korpatsch.

[48] She then accepted a wildcard into the Andorra Open, where she defeated sixth seed Sara Errani in the first round,[49] but lost to Alycia Parks in the quarter-finals.

She broke the record of 24, held jointly by Serena Williams and Kaia Kanepi, by hitting 27 aces during her second-round encounter against Belinda Bencic at the 2015 Aegon Classic on 17 June 2015.