Grigor Dimitrov
Grigor Dimitrov had his best ever season in 2017 winning 4 titles including his maiden ATP 1000 title at Cincinnati as well as the ATP Finals. He ended the year as World No. 3. At this time last year, the Bulgarian had won 2 titles however he has reached only one final so far in 2018. More worrying is that he is losing earlier in tournaments than he did last year. Once considered as a future World No. 1 and Grand Slam champion, the 27-year old is rapidly running out of time to make his mark and is now the World No. 6.
Alexander Zverev also had his best season in 2017 winning 5 titles including 2 ATP 1000 titles at the Italian Open and the Canadian. He reached a high of World No. 3 before ending the year as World No. 4.
The 21-year old has done well in 2018 winning his third ATP 1000 title at the Madrid Open joining the Big 4 in being the only active players to have won three or more ATP 1000 titles. He reached his first Grand Slam quarter-final at the French Open and reached the finals at the Miami Open and the Italian Open. He is back to World No. 3 and the second half of 2018 looks promising for the German.
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