By this time last year, Juan Martin Del Potro had not won any titles. So far in 2018 Del Potro has won 2 titles including his first ATP 1000 title at Indian Wells in a close final against Federer. He reached the semi-finals of the French Open and reached his highest ranking of World No. 4. It has been one of the best years for Del Potro and if the Argentinean can stay healthy then he can be a contender for any title in the second half of 2018.
Dominic Thiem won one title this time last year while he has won two so far this year. He reached the Madrid Open finals both years and is the only player to beat Nadal on clay in both 2017 and 2018. He reached the finals of the French Open which improvd upon his semi-final showing in 2017. Primarily a clay court player, he is effective on hard courts and is expected to do well in the second half of 2018.
There were a couple of surprise performers this year. Chung Hyeon and Kyle Edmund reached the semi-finals of the Australian Open becoming the first time that two unseeded players reached the semi-finals of a Grand Slam since Wimbledon 2008 and first since 1999 at the Australian Open. Both have shown promise and have potential. The surprise performer of 2017, Dennis Shapovalov, has continued to improve and has entered the top 30.
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