* U.S. data in focus, especially Friday's jobs report
* U.S. Treasury yields reaction to economic data eyed
By Kaori Kaneko
TOKYO, Jan 4 (Reuters) - The dollar edged down from a four-month high against the yen but held firm against other majors on Monday, the first trading day of 2010, as investors focus on U.S. data this week that could add to optimism about the economy.
Investors are set to take cues from the U.S. December employment report on Friday as well as figures from the manufacturing and service sectors.
"The main focus for market players is the direction of the dollar now that year-end buying is no longer around to give the greenback support," said Minoru Shioiri, chief manager of FX trading at Mitsubishi UFJ Securities.
"And the reaction of U.S. yields to the upcoming data will be key for dollar/yen," he said.
Higher longer-dated U.S. Treasury yields underpinned the dollar's recent gains against the yen, traders said, with benchmark Treasury yields rising above 3.9 percent on Thursday, in sight of last year's high around 4 percent.
The U.S. non-farm payrolls report is expected to show U.S. employers cut 20,000 jobs in December, according to economists polled by Reuters, after the economy shed a much lower-than-expected 11,000 jobs in November.
The dollar was trading around 92.84 yen, having risen as high as 93.15 yen on trading platform EBS last Thursday, its highest since early September 2009.
The dollar index, a gauge of the greenback's performance against six other major currencies, inched up 0.2 percent to 78.004.
The euro was trading around $1.4302, down 0.1 percent from U.S. trading on Dec. 31.
Yen crosses were lower with the euro slipping 0.4 percent to 132.74 yen. (Reporting by Kaori Kaneko; Editing by Edwina Gibbs)