(CNN) -- World number one Dinara Safina and fellow-Russian Elena Dementieva are through to the second round of the Porsche Grand Prix in Stuttgart, although they suffered varying fortunes on Tuesday.
Dinara Safina celebrated her first match as world number one with a crushing firsat round victory in Stuttgart.
Top seed Safina, who turned 23 on Monday, celebrated her first match on top of the rankings with a 6-0 6-1 crushing of Italian Sara Errani.
Safina will now play either France's Alize Cornet or Slovakia's Daniela Hantuchova in the second round after her 51-minute victory.
In contrast, Olympic champion and second seed Elena Dementieva needed more than two hours to scrape past local favorite Anna-Lena Groenefeld 6-4 3-6 6-3.
In the other first round matches, eighth seed Agnieszka Radwanska of Poland needed a first set-tie break against Aleksandra Wozniak before beating the Canadian 7-6 6-0.
China's Na Li beat compatriot Shuai Peng 6-2 6-3 while Bulgaria's Tsvetana Pironkova also took her place in the second round with a strong comeback as she won 0-6 6-4 6-4 against Italy's Alberta Brianti.