Stan Wawrinka, Milos Ranic, and Kei Nishikori all called time on their 2017 campaign and returned in 2018 with varying degrees of success.
Stan Wawrinka had knee surgery and has been struggling, mostly losing in the first or second rounds. His best showing was a semi-final loss at the Sofia Open.
Milos Raonic has performed slightly better reaching the finals of the Stuttgart Open losing to Federer. He also reached the semi-finals of Indian Wells however withdrew from the French Open due to a knee injury and retired from the Queen’s Club Championships due to injury.
Kei Nishikori returned from wrist injury by playing a couple of challenger tour events and won one of them. He has shown steady improvement and reached the finals of the Monte-Carlo Open losing to Nadal.
They are all scheduled to play at Wimbledon and it remains to be seen as to how they will perform for the rest of 2018.
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