to the 16-Grand Slam titles holder Roger Federer. He went 23–18 on the season and earned $513,955. 2011 Mayer started the new season in style. In preparation for the Australian Open. he reached the quarterfinals of the Brisbane International and the semifinals of the Medibank International in Sydney. 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 weeks later, he came through to his second semifinals of the year in Zagreb. On his way to this stage, he defeated top seed Marin Čilić, 6–3, 6–4. He lost the semifinal against countryman Michael Berrer. With this result, he was the new German no. 1 in the ATP ranking. At the 2011 BMW Open in Munich, Mayer reached his fourth career final. He was again not able to capture his maiden ATP World Tour title, after losing to Nikolay Davydenko in three sets. Two days after this loss, he managed to beat Viktor Troicki in three sets in the first round of the Mutua Madrid Open. He had to retire in the second round against Thomaz Bellucci. He rose to a new career-high rank of no. 28. Mayer reached the quarterfinals of the Italian Open in Rome. After three straight-set wins, Mayer could not keep up the momentum against Andy Murray, after having won the first set. He went on to lose, 6–1, 1–6, 1–6. Again he rose to a new career-high rank of no. 21. By winning three out of three matches at the World Team Cup in Düsseldorf, Mayer was the key player in the German team to capture the trophy for the fifth time. He improved to no. 19. 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. In addition, he lost his Davis Cup quarterfinal match against Richard Gasquet, despite serving for the match in the third set. 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. Mayer then reached the third round in the