* Exporters fall on earnings worries due to strong yen trend
* Fast Retailing surges on Sept sales jump, upgrades
* Nomura, financial shares regain ground after sell-off
* Trade light; eyes increasingly on earnings season -analysts
TOKYO, Oct 5 (Reuters) - Japan's Nikkei average hit a 10-week low on Monday, dented by shares of exporters on concerns over the fragility of the U.S. economic recovery and lingering worries about the yen's recent strength.
But a surge in shares of Fast Retailing, which saw domestic same-store sales at its Uniqlo casual-clothing chain jump 32 percent in September, provided support to the benchmark index, which earlier moved in and out of negative territory.
"With eyes increasingly on corporate earnings reports for the first half of Japan's business year, investors are betting the stronger yen will no doubt drag on exporters' outlooks," said Masayoshi Okamoto, head of dealing at Jujiya Securities.
In see-saw trade, the Nikkei dipped 0.4 percent to 9,692.24, after falling as far as 9,671.39, its lowest since July 22.
The broader Topix slipped 0.9 percent to 866.41.
Weaker-than-expected U.S. jobs data weighed on investor confidence, although analysts said the numbers had not drastically altered expectations that the U.S. economy would recover gradually.
"While the data was bad and optimism about the U.S. economy may have receded, I do not think market players think that this means that the outlook for the U.S. economy is ruined," said Hideyuki Ishiguro, supervisor at Okasan Securities' investment strategy department. "I think it just means market sentiment has returned to neutral for the time being," Ishiguro added.
The Nikkei fell 5.2 percent last week, its worst weekly loss in about three months. It has fallen below trendline support drawn from its March trough near 7,021 and through its July low near 9,050, and on Friday the benchmark index dropped below the bottom of the cloud on daily Ichimoku charts.
Some analysts say the next downside target may be 9,500, with a break below that opening the way for a drop towards its July low of 9,050.
EXPORTERS DOWN; BANKS, FAST RETAILING UP
Banking shares rose after having recently been battered by worries that lenders may come out with share offerings in the face of a global regulatory push for banks to carry bigger capital buffers.
Top bank Mitsubishi UFJ Financial Group climbed 1.8 percent to 453 yen and Mizuho Financial Group added 2.3 percent to 178 yen. The banking sector subindex rose 0.5 percent.
Nomura Holdings shot up 5.6 percent to 564 yen. Shares of Japan's largest brokerage plunged after it last month unveiled a $5.6 billion share sale plan aimed partly at meeting tougher capital requirements.
"Short-covering after a sell-off is buoying financial shares," said Mitsuo Shimizu, deputy general manager at Cosmo Securities.
"Investors are also betting Nomura's share sales price will be decided soon, possibly today. Usually, selling on worries about the erosion of demand and supply tends to run its course once such prices are set."
Fast Retailing soared 16.4 percent 13,710 yen. The big jump in sales was helped by the onset of cold weather which boosted demand for autumn goods and by a five-day weekend in September.
Following the strong monthly sales, Morgan Stanley raised its rating to "overweight" from "equal-weight", and UBS lifted the firm to "buy" from "neutral".
Exporters retreated on lingering concern that the yen's recent strength will curb their overseas profits. The yen stood around 89.80 yen to the dollar. It hit an eight-month high of 88.23 yen to the greenback last week.
Sony Corp slid 2.2 percent to 2,395 yen and Nikon dropped 6.4 percent to 1,451 yen, while Honda Motor shed 2.3 percent to 2,610 yen and Toyota Motor Corp fell 0.9 percent to 3,350 yen.
The head of Toyota on Friday called the current dollar-yen rate "very tough", and Honda Chief Executive Takanobu Ito said on Thursday said that a dollar below 90 yen was "too painful".
Defensive sectors were higher, with some analysts saying worries about the impact of the strong yen on exporters' earnings may be prompting investors to buy shares of companies that are less sensitive to currency moves or that may benefit from a stronger domestic currency.
KDDI Corp, Japan's No.2 phone operator, rose 1.6 percent to 514,000 yen and NTT DoCoMo climbed 1.2 percent to 141,800 yen. (Reporting by Aiko Hayashi and Masayuki Kitano; Editing by Joseph Radford)