Professional athletes in the United States are boycotting matches to protest against racial injustice  following another police shooting of a black man in Wisconsin.

Today’s NBA playoffs, WNBA games and some Major League Baseball matches have been postponed as players protest the shooting of unarmed black man Jacob Blake who shot in the back by police.

Milwaukee Bucks players refused to leave their team dressing room before game five of their first-round playoff series against the Orlando Magic, with confirmation of the boycott coming through soon after.

Tennis has also been impacted with two-time grand slam winner Naomi Osaka pulling out of her semi-final at the WTA Western and Southern open in protest.

Nine News Perth sport reporter Paddy Sweeney explained the situation: