Monfils into Legg Mason semi-finals

Top seed Gael Monfils advanced to the semi-finals of the Legg Mason Tennis Classic but the other high seeds tumbled in Washington.

Monfils saw off sixth seed Janko Tipsarevic 6-4 6-4 to advance.
He will now face 11th seed John Isner after the American saw off number three Viktor Troicki 7-6 (7-5) 3-6 6-1.
There will be an unseeded finalist after Donald Young and Radek Stepanek advanced on the other side of the draw.
Young beat seventh-seeded Baghdatis 6-4 7-6 (7-4) and Stepanek was a 6-4 6-4 winner over the fifth seed Verdasco.