GRAINS-Soybeans on track for worst week since Oct on Argentina rains

* Soy has fallen more than 2 pct so far this week

* Wheat gains after U.S. export sales beat forecasts

(Adds more analyst comment, U.S. export sales, updates prices) MANILA, Dec 15 (Reuters) - U.S. soybeans ticked higher on Friday, but were still on course for the biggest weekly loss in almost two months on expectations of rains in Argentina, the world's third biggest supplier. Wheat prices, which touched an 11-month low this week, also edged up on strong U.S. export sales. Corn was steady. Soybeans for March delivery on the Chicago Board of Trade were up 0.2 percent at $9.69-1/4 a bushel by 0358 GMT. They have lost 2.1 percent so far this week, the most since the week ended Oct. 20. The market had been supported by worries over dry conditions in some of Argentina's soybean regions, but "weather forecasters have become more confident that weekend and subsequent rain events will dispel these worries," Commonwealth Bank of Australia analyst Tobin Gorey said in a note. "We suspect the response in terms of lower prices is incomplete," said Gorey. Argentina's Rosario exchange raised its 2017-18 wheat crop estimate to 17.3 million tonnes compared with 16.3 million tonnes previously, the exchange said on Wednesday, citing higher-than-expected yields. The Buenos Aires Grains Exchange, however, said the drought that has blighted Argentina's Pampas farm belt since November could still lead to a cut in the estimated 2017/18 soybean planting area.

Chicago March wheat rose 0.4 percent to $4.19-3/4 a

bushel, well above Tuesday's trough of $4.10-1/2, the lowest since early January. The contract was little changed for the week. The U.S. Agriculture Department reported weekly wheat export sales of 588,800 tonnes, topping trade forecasts that ranged from 250,000 tonnes to 450,000 tonnes. A week ago, wheat export sales were 323,034 tonnes.

Corn was flat at $3.48-3/4 per bushel, down more than

1 percent on the week. U.S. weekly export sales of corn reached 866,900 tonnes, down 1 percent from the previous week. Soybean sales of 1.45 million tonnes were down 28 percent from a week ago.

(Reporting by Manolo Serapio Jr.; Editing by Sherry Jacob-Phillips and Tom Hogue)