NEW YORK. Sept 8 (Reuter) World number one Steffi Qral continues to astonish even those closest to her with an amazing ability to keep win ning while her personal world is falling apart

Once again on Saturday. Just two after the start of her father s trial on tax evasion charges in Germany. Graf managed to keep her focus on tennis long enough to advance to her fourth consecutive US Open final.

How she goes and pulls It to gether... if 1 knew the recipe 1 would be the greatest coach In the world.'' Grafs coach. Heinz Gunthardt. said with wonder and admiration

The trial began on Thursday with the tennis superstar's father facing a possible 10 years in prison if convicted.

"Sometimes she can't get her head together on the court. Five minutes she will hit well and she then will hit it all over the place. It makes it very difficult tor her to practice," Gunthardt said

"I am unusually somebody that starts well from the begin ning on so that is not my character." admitted Graf, who had to stave off five set points in the first set against Hingis.

"Not one of those set points she saved can you say she got a present from Hingis,'" said Gunthardt. "You can’t say Hingis choked.

"At crunch time Steffi knuckled down. That’s the mark of a champion."