Stan Wawrinka has decided to withdraw from the Miami Open and Indian Wells tournaments so that he can continue his recovery from a persistent knee injury.
The 32-year-old returned to action in January at the Australian Open after a five-month spell on the sidelines.
However, the three-time grand slam winner was beaten in the second round in Melbourne and admits he is still some way short of full fitness.
"They are both amazing events, but coming back from a big surgery after having played a few tournaments, I have discussed with my team that it is best for me to build on the progress and go back to practice," Wawrinka said in a statement.
"I have enjoyed being back on tour playing matches and this gives me even more motivation to go back on the practice court. My goal is to find my highest level again and, in order to do that, I will keep working hard every single day."
French duo Richard Gasquet and Jo-Wilfried Tsonga have also withdrawn from Indian Wells due to knee injuries.
Jeremy Chardy, Laslo Djere, and Lukas Lacko have replaced the injured trio in the main draw.
Meanwhile, Alexander Zverev is 15/8 to win the Acapulco Open and Kevin Anderson can be backed at 2/1.
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