Naomi Osaka exits Toronto Open with back injury

Naomi Osaka’s recent struggles continued Tuesday with an early exit at the National Bank Open.

She is a four-time Grand Slam singles champion.

She has been ranked No. 1 by the Women's Tennis Association and is the first Asian player to hold the top ranking in singles.

She was trailing 7-6 (4), 3-0 against Estonia’s Kaia Kanepi when she withdrew from the contest.

I felt my back pain from the start of the match, and despite trying to push through it, I just wasn’t able to today,” Osaka said.

Osaka said, “I’d like to pay credit to Kaia for playing well and want to wish her all the best for the rest of the tournament.”

Entering the tournament, Osaka had been eliminated from her last three competitions in the first or second round.