Valerie Vili has run into marital troubles, compounding a tough year marred by seven consecutive defeats and a breakup with her long-time coach.

The champion shot-putter yesterday announced she was dropping her married name, Vili, and asked to be called Valerie Adams in the future.

Her manager, Nick Cowan, confirmed the name change had resulted from tensions with her husband, Bertrand Vili.

"The only comment that I can make is Valerie and Bertrand are experiencing difficulties at this time, and Valerie asks that her privacy is respected in relation to that," Mr Cowan said.

Adams, 25, and Vili, a New Caledonian discus thrower, married in 2004.

She went on to win gold at the 2007 Osaka world championships and the 2008 Beijing Olympics.

This year, however, she has struggled, consistently losing to Belarussian rival Nadezdha Ostapchuk since March, when she lost for the first time in almost two years.

Adams was again beaten by Ostapchuk at an event in Zurich yesterday, her seventh straight defeat to her arch-rival.

She lost despite a best mark of 20.02m - an improvement from her previous meets - but fell short of Ostapchuk's 20.63m.

Adams won at Beijing with a throw of 20.56m.

In April, she broke up with coach Kirsten Hellier, who had mentored her since she was aged 14. She said she needed "new input" to keep up her winning form.

Adams fought back tears at a press conference at the time, saying it was a purely professional decision to part ways with Hellier.

Mr Cowan said Adams had been steadily improving under new French coach Didier Poppe, and the pair were happy with their preparations for the Commonwealth Games in New Delhi in October.

Adams has finished her Diamond League events for the year, and moves on to a minor meeting in Slovakia next weekend.

She will compete in the Continental Cup - traditionally called the World Cup - in Split, Croatia, next month before finishing her year at the Commonwealth Games.

Mr Cowan said: "It's been quite a long year for her."