Hewitt was made to battle hard against his opponent and eventually clinched his win on his fourth match point.

Both players produced some fabulous tennis and the initiative ebbed and flowed during a three-hour match which enthralled the capacity crowd in Shanghai.

Federer was in pole position in the first set when he led 5-3 but he let his concentration lapse and Hewitt won four games in a row to take it 7-5.

In the second set, it was Federer's turn to prove his fighting qualities.

He came from a break down twice and saved one match point on Hewitt's serve at 4-5.

He then held serve to lead 6-5 and broke Hewitt's serve on his fourth break point to take the set.

There was more excitement in the decider as the Swiss player came back from a break down twice and saved two more match points.

But his brave performance finally came to an end when he sent a forehand long on Hewitt's fourth match point.

The look of relief on Hewitt's face at the end was testament to the titantic struggle he had faced.

Hewitt will now face Spain's Juan Carlos Ferrero in Sunday's final as he bids to defend his title.