In the week that Google closed its search engine on the Chinese mainland, its former rivals have been keeping low-key, despite mounting speculation over how it leaves the market.

Home-grown giant Baidu has emerged as an almost unchallenged leader in the short term. According to Analysis International, a leading Chinese Internet consulting company, Baidu occupied 58.4 percent of the market at the end of last year, whereas Google took 35.65 percent.

However, calls to Baidu's public relations department regarding the changing market have gone unanswered.

Jin Jianbin, associate professor at Tsinghua University, said the market situation would definitely change -- but Baidu may not be the main beneficiary.

"Internet users don't want to see a monopolized market, so they may turn to smaller engines instead of sticking with Baidu," said Jin, who specializes in network information studies.

"Microsoft's Bing may have a big opening," he said.

Google announced Tuesday that it had stopped censoring its Chinese-language search engine Google.cn and redirected mainland users to its Hong Kong site.

However, the mainland users have found access to the new search portal was very unstable.

"It will affect individual users and some of Google's clients, when they are uncertain about the search engine service's future, and its other services, such as maps and mail services," said Dr. Hu Bo, of the School of International Studies of Peking University.

Analysts believe Sohu's Sogou, Tencent's Soso and other newcomers, including Bing and Taobao's independent search engine, are all eyeing the vacancy left by Google and will see an obvious increase in market share.

Microsoft officials would not discuss its search business prospects in China, but said Thursday that it had done business in China for more than 20 years and it intended to continue that business.

"We also regularly communicate with governments, including the Chinese, to advocate for free expression, transparency, and the rule of law. We will continue to do so," it said in an e-mail to China Features.

Qiao Peilei, a public relations officer with Taobao refused to comment on its search engine's prospects. She said Taobao's e-commerce business had nothing to do with Google's exit.

Jin Jianbin said that in comparison with their mainland counterparts, foreign search engines had a greater appeal to loyal users of Google, who might turn to another international engine if Google's Chinese language search service was unstable or unavailable in the future.

Leung Mantao, commentator with Hong Kong-based Phoenix TV, said that unlike Baidu's marketing combination of e-business, content provider, and information search, Google focuses on information search. No other company could yet compete with Google in information search in terms of quality, range and reliability of search results.

"Therefore, those willing to focus on developing information search services in the future will have the potential to take Google's share," he said.

And in English or other foreign language search fields, Baidu was just not competitive. So for Chinese companies doing overseas business, Google was still a better choice for advertising, Leung said.

Experts have other worries over the mainland search engine market without Google.

Bu Ziqin, search engine analyst with China e-Business Research Center, said Google's balancing and pioneering impact on the Chinese Internet market would be weakened, or even lost.

Hu Bo, who also studies e-business, said that as the only big shot in a market without Google, Baidu would have a decisive influence in setting new rules.

"It will consider the company's benefits as top priority when making rules, if it has no outside restrictions, which would be devastating to the whole industry," Hu said, referring to the "Baidu Bidding Rank", the old pay per click program that was criticized both by Internet users and industry experts for selling organic search results to advertisers.

Jin Jianbin said search engine companies were more than a business.

"They are social fundamental infrastructure, just like railways and expressways, so they should bear more social responsibility," he said.

Hu Bo suggested the government should make standards for the industry, for example, setting rules on advertising.

"Actually, the government has much more to do in monitoring the search engine market after Google's exit," Hu said.

The government would also have to ensure Baidu would not monopolize the market, he said.

Leung Mantao said Google's exit signaled no changes in the investment environment of the Chinese mainland, but the Chinese government should make laws and regulations clearer.

"In this way, it's easy for companies, both international and domestic, to follow them," Leung said.