The biggest win of his career came at the 2011 Shanghai Rolex Masters when he upset twenty-time Grand Slam champion Rafael Nadal in the round of 16.

[2] Florian made a return from injury reaching the final of the Nouméa Challenger but losing to Brendan Evans.

Mayer then qualified for the main draw of the Australian Open by beating Sergey Bubka, Blaž Kavčič and Amer Delić.

Mayer reached the final at the If Stockholm Open, after beating Jarkko Nieminen in a tight semifinal, saving a match point.

5 Robin Söderling and two-time Wimbledon quarterfinalist Feliciano López en route to the final, where he lost 4–6, 3–6, to the 16-Grand Slam titles holder Roger Federer.

At the first Grand Slam tournament of the season in Melbourne, Mayer surprisingly defeated Doha finalist Nikolay Davydenko in four sets, only to lose against Japanese Kei Nishikori in the second round.

Two days after this loss, he managed to beat Viktor Troicki in three sets in the first round of the Mutua Madrid Open.

The German, however, could not overcome the second round of Roland Garros and Wimbledon, losing in fourth sets in both cases against Alejandro Falla and Xavier Malisse, as he did in the Australian Open.

Two weeks later, he reached the Hamburg ATP 500 quarterfinals, losing in straight tiebreaks to third seed Nicolás Almagro.

However, in the ATP World Tour Masters 1000 of Montreal and Cincinnati, he lost in first round to Richard Gasquet and Ivo Karlović, respectively.

He couldn't win consecutively until the Miami Masters, where he defeated Ivan Dodig and Indian Wells finalist John Isner.

[3] Mayer reached quarter-final of Shanghai Masters and defeated French Open finalist David Ferrer.

He defeated Michał Przysiężny, then third seeded Andy Murray who returned from injury layoff, then Victor Hănescu who upset Fernando Verdasco.

Mayer won the Gerry Weber Open in Halle, defeating Andreas Seppi in the quarterfinal, world No.

Mayer played his last match on the ATP tour at the 2018 US Open, losing to Borna Ćorić in four sets in the first round.

He has an unusually long take-back on both his forehand and two-handed backhand and generally hits more top-spin than flat on both wings.

Mayer's biggest weaknesses are his lack of match consistency and fitness, having had inconsistent results throughout his career and a relatively small build.