US Treasury prices fell for a fourth straight session on Monday as investors worried that a week packed with economic data, culminating in the March jobs report, could spell trouble for bonds.
Due out on Friday, the Labour Department's payrolls report is expected to show that companies are finally starting to take on new workers, albeit slowly, after a prolonged hiring drought.
Few doubt that such an outcome would bring a recent rally in bonds to a screeching halt.
For the Treasury market, which thrives when the economy is weak, signs of employment growth would be viewed as giving the Federal Reserve leeway to begin raising interest rates.
"People are getting defensive, setting up for payrolls," said Gerald Lucas, chief Treasury strategist at Banc of America Securities.
"We live from payroll to payroll and the market fiddles around in between."
A report that Japan had ended its massive currency intervention campaign also rattled a market that has grown reliant on demand from foreign central banks.
The Times of London quoted a Bank of Japan official as saying Japan's intervention campaign had come to an end.
Ministry of Finance officials were quick to note that they control foreign exchange policy, not the central bank and flatly denied the statement, vowing to intervene as needed.
But that came too late to stem the damage to prices, with benchmark 10-year notes sliding 14/32 for a yield of 3.89 percent from 3.84 percent late Friday.
Traders were already suspecting Japanese interest in US debt was fading, with Federal Reserve custody holdings for foreign central banks showing the first decline in 22 weeks last week.
Five-year notes slipped 8/32, taking yields to 2.84 percent from 2.79 percent.
The 30-year lost 24/32, driving its yield to 4.81 percent from 4.76 percent.
At the very short end, yields on two-year notes edged up to 1.62 percent from 1.58 percent.