THEIR home is a large bathtub, otherwise known to national sailors Xu Yuanzhen and Terence Koh as a 470.

It is where they spend hours at sea together, plotting and planning, and bickering like an old married couple.

The pair do not disagree with the comparison. But just don't ask them who is the woman in the relationship.

'It's him without a doubt,' declares Xu, 23, the helmsman. 'He definitely wears the skirt. He moans a lot more. He's the moody one and I've to take all the abuse.'

To which Koh, 20, counters: 'Who's the one who tried to play hard to get?

'I had to beg him to partner me, not to mention the many lunches and dinners he got out of me in the process.'

Regardless of who did the wooing - in case anyone is wondering, they both have girlfriends - theirs is clearly a partnership that works.

For the uninitiated, the 470 boat is a maze. Its nerve centre consists of 40 controls, with about 20 ropes of various colours designed to make the boat respond to the sailor's every move.

Coupled with the fact that sailing is a sport in which the conditions constantly change, punishing the slightest error, it can get quite tense.

Says Xu: 'They are times when we'd be absolutely furious with each other.

'But we know better than to let arguments affect the race. It usually takes about 10 seconds for us to cool down - one of the reasons that we've managed to do well.'

The pair also complement each other. It was Xu's good steering skills which attracted Koh and suited his more tactical approach to the sport.

Less than a year after they said 'I do' as helmsman and crew, the duo won a silver medal at the 2006 Doha Asian Games, after beating the more experienced pair of Roy Tay and Chung Pei Ming for a spot on the Asiad team.

It fuelled an already growing belief that they could feature at the Olympics - a feat they achieved last month when they again edged out Tay and Chung after a series of three trials.

Both pairs had qualified for the Olympics, but only one team could go to Beijing.

Says full-time national serviceman Koh: 'The trials really prepared us well for the Olympics because we experienced everything in those races.

'Yuanzhen was down with stomach problems during the first trial. I was so ill during the second trial that I couldn't even talk.'

Trailing Tay and Chung going into last month's Open 470 European Championships, the third and final trial, the pair finished 34th among 91 boats to leapfrog their compatriots, who had begun the event 17 points ahead with 57 points. Tay and Chung finished 53rd with a 110-point total, two above the pair's 108.

Says Xu, who has put his studies on hold to train full-

time: 'It was the toughest race we've ever sailed, knowing the pressure was on to finish as high as possible.

'But at least now we know we can put in a strong performance when it matters.'

The sailing format in Qingdao will feature, for the first time, a medal race of the top 10 qualifiers.

Xu and Koh - having finished 13th in a world-class field at an Olympic test event last year - are Singapore's best bet for a final place.

It is something this pair aim to achieve - for better or for worse.