Ashleigh Ball cannot play it straight for the GB hockey girls in tonight's hair-raising semi-final against Argentina.

The Brighton-born star has to keep her curls in, because of superstitious team-mate Laura Unsworth.

Ball has been banned from using her hair straighteners by Unsworth, as she believes it jinxed the side in a previous game.

Unsworth also insists on going to toilet at certain times before a match.

Ball said: "She's convinced we have lost games before, because of her change of routine. She is very superstitious, which I'm not.

"I joked the other day that I was going to straighten my hair and she nearly hit the roof. She has got a real bee in her bonnet about it."

Ball has been influential for GB, scoring in a 3-0 victory against Belgium and setting up a goal for Crista Cullen with a penalty corner in the 2-1 defeat by the Netherlands on Monday.

Argentina are ranked two in the world behind the Dutch, who are already through to the final to decide gold or silver on Friday night (8pm).

They beat New Zealand 3-1 in the shoot-out in this afternoon's first semi-final following a 2-2 draw after-extra-time.

This evening's losers play-off against New Zealand for the bronze medal on Friday afternoon (3.30pm).