Serena Williams has been handed the maximum possible fine by US Open officials following her verbal abuse of a line judge in her semi-final with Kim Clijsters.

Serena Williams insists she can learn from her mistakes after a row with a lineswoman sent her crashing out of the US Open.

Kim Clijsters moved into the US Open women's singles final in controversial circumstances as defending champion Serena Williams picked up a point penalty for a second code violation on match point against her.