April 24, 2014 12:43 PM EDT

Serena Williams has been playing tennis since the age of four and has established herself as one of the greatest female players of all time, having racked up 32 major titles in her career.

“I always try to stay positive through the ups and downs and try to keep a smile on my face,” she says.

Despite a number of controversies and injury setbacks, Williams is competing in a number of tournaments this year and took time out to talk to TIME about the biggest influence on her life and career.

Contact us at editors@time.com.

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