JGB futures tumble as foreign funds sell before roll

* Futures tumble nearly a full point in thin trade

* Traders cite foreign funds dumping futures before roll

By Satomi Noguchi

TOKYO, Sept 4 (Reuters) - Japanese government bond futures tumbled nearly a full point on Thursday with traders citing selling by foreign funds in a move exaggerated by thin trade.

September 10-year futures plunged as much as 0.93 point to 137.42 2JGBv1 as market players suspect that hedge funds sold a large amount of the futures abruptly. The move may also be tied to the lead contract's roll next week.

"It may be related to investors dumping futures because the market hasn't risen as much as they wanted and they didn't want to hold futures until the roll-over," said a dealer at a Japanese bank.

"It may also be that some investors were worried after news of hedge funds crumbling due to slumping commodities and decided to book profits in a hurry."

The lead contract fell 0.56 point to 137.79 2JGBv1, retreating from a four-month high of 138.80 last week. Some said futures sellers may be trying to hedge upcoming five-year utility bond issues.

The benchmark 10-year yield JP10YTN=JBTC climbed 4 basis points to 1.495 percent and jumped as high as 1.515 percent, pulling up from a four-month low of 1.400 percent hit on Friday.

The five-year yield JP5YTN=JBTC jumped 6 basis points to 1.060 percent and touched as high as 1.070 percent.

The two-year yield JP2YTN=JBTC edged up 1.5 basis points to 0.735 percent while the 20-year yield JP20YTN=JBTC rose 3.5 basis points to 2.115 percent.

Market players were wary of more unpredictable moves before comments from the European Central Bank and Bank of England later in the day.

Analysts said the market is watching to see how those central banks address the deteriorating global economic outlook and how the local bond market reacts.

(Additional reporting by Chikako Mogi, Shiho Tanaka)