Stuttgart, Germany - China's 110m hurdles world record holder Liu Xiang and Jamaica's 100 metres world record holder Asafa Powell made the most impressive marks on the opening day of the IAAF World Grand Prix finals.

Powell ran yet another sub 10 second race though he didn't threaten his record of 9.77sec and Liu made a stunning return to the international circuit after taking time off since breaking the world mark in July in Lausanne.

Xiang Liu of China celebrates after winning the 110 metres hurdles event at the IAAF World Athletics Final in Stuttgart September 9, 2006. [Reuters]

Liu timed 12.93sec in the event and admitted to not feeling too surprised at his excellent run.

"I felt really well before the race and I knew I was in really good shape," said the 23-year-old Olympic champion.

"After my world record (12.88sec breaking Colin Jackson's 13 year old mark of 12.91) I returned to Beijing and got a lot of rest," added Liu.

However Liu promised more of the same at the World Cup in Athens next weekend.

"The World Cup has been my end of season objective and that is why I didn't give it my all," said Liu.

Unlike Liu, Powell was undecided about the World Cup.

"I feel a little tired, the season has been long but a rich one," said Powell, who started way back in March at the Commonwealth Games where he won the 100m title.

"I will see whether I run in Athens next week."

Powell admitted that he had not threatened his world record because he was nervous of false starting.

"There had already been one so I didn't want to be disqualified for doing the second one. I am not disappointed in my time at all."

Elsewhere America's Olympic and world 400m champion Jeremy Wariner continued his dominance of the event as he won with something in hand.

"It has been a long season but my best run since London," said Wariner, who is with Clyde Hart the coach of world record holder Michael Johnson.

"It is a great way to finish the season but I had to dig down deep."

His performance spurred on Democratic Republic of Congo runner Gary Kikaya, who broke Nigerian Innocent Egbunike's 19-year-old African record in the 400 metres.

The 28-year-old timed 44.10 seconds in finishing second to Wariner eclipsing Egbunike's time of 44.17sec set in August 1987.

Kikaya, who was formerly coached by controversial handler Trevor Graham, said he was delighted to have run Wariner so close.

"I am surprised nevertheless to have been so close to him (Wariner)," said Kikaya, who is one of eight children and lived in South Africa for 10 years when his father was ambassador there.

"However it is only human to try."