Dementieva serve the key

Dementieva's form has been patchy so far in the tournament, though the final two sets in her 4-6 6-1 6-1 quarter-final win over Bethanie Mattek were filled with some blistering groundstrokes from the 24 year-old Muscovite.

Her serve, though, proved a liability again as she fired down a total of 14 double-faults Demtieva herself admitted a repeat performance would cost her dearly against Sharapova:

"It's all about her concentration. She plays every ball like it's the last one and she doesn't give you an easy point. You have to work hard against her. Whether I can hold my serve will be the big question."

The 19 year-old former Wimbledon champion has looked imperious so far in her journey to the last four, and disposed of world number 15 Dinara Safina 6-2 6-4 in the quarter-finals.

In the pair's last meeting at Wimbledon, Sharapova preyed on her compatriot's weak second serve, lashing winners past her opponent almost at will on her way to a comfortable victory.

Once the ball is in play, both women are among the strongest hitters off the baseline on the Tour, though unless there is a marked improvement on Dementieva's serve, it could be plain sailing for her younger opponent.