Naomi Osaka casts doubt on tennis future after first-round defeat in Miami

Osaka admits to dilemma after loss to Talia GibsonNorrie, Boulter and Jones all out to end British hopesNaomi Osaka has said she does not intend to continue competing if she frequently loses in first round matches after suffering a disappointing 7-5, 6-4 defeat to Australias Talia Gibson in her opening match of the Miami Open.Osaka, who received a first-round bye as the 16th seed in Miami, moved sluggishly in an error-strewn performance and was outplayed by the talented 21-year-old Gibson, who w...