The City of Edinburgh swimmer tied for second place with America's Megan Jendrick on day six in Australia thanks to a strong finish after a bronze had looked the likeliest of outcomes.

Double world record holder Leisel Jones claimed the title in front of her home crowd in 2min 21.84sec with Balfour and Jendrick home in 2:25.94.

"That really hurt me," said Balfour.

"All I could think about was keeping it going and getting to the wall. It was a hard race but I'm so happy with the silver.

"It's what I came to Melbourne to get.

"I was with Leisel at the 100metres mark and then she just took off and left the rest of us behind.

"I held my reserve though, didn't panic and finished it off although it doesn't get any closer at the end with Megan."

The 23-year-old's calm approach paid off as she was able to stick to her race plan.

"I was really trying to hold my stroke and I was pleased with that, it was long and I didn't panic," said Balfour, the European champion.

"I kept my form throughout because I knew that would get me where I wanted to be.

"Before the event I didn't feel nervous, in fact I was very relaxed and that helped me.

"You need that especially with the breaststroke events.

"I was just grateful for the opportunity to be there and to perform as I did.

"I was hoping to do a best time here but I did enough to get a medal so I'll leave next week knowing I'm going in the right direction."

The men's 4x200m freestyle team set a new British record as they finished fourth.

The quartet of Dave Carry, Robbie Renwick, Simon Burnett  and Ross Davenport came home in 7:11.28 while the medals went to the USA with gold in a new world record time of 7:03.24, Australia the silver in 7:10.05 and Canada the bronze in 7:10.70.

Carry said: "We finished out of the medals but we went faster than we've ever been before and considering we've all had indifferent weeks that's a big positive for us.

"We had to go for it tonight from lane one and we did just that."

Burnett said: "That hurt. That was all heart out there and all of us stepped up our performances.

"It's always exciting racing with this relay team, they're such a great bunch and I know we can take this relay forward.

"Beijing's around the corner and we can build on what we've achieved."

Stockport's James Goddard and Edinburgh's Gregor Tait finished sixth and eighth respectively in the 200m backstroke.

Goddard clocked 1:58.88 with Tait finishing in 1:59.41 in a race won by American Ryan Lochte in a new world record of 1:54.32, ahead of team-mate and defending champion Aaron Peirsol and Markus Rogan of Austria.

"I gave it my best shot on the night. It wasn't good enough but I know why and that's because I've had very little preparation," said Goddard.

"I'll move to Loughborough full-time when I get back and it's a change I need to make.

"I now realise what I'm capable of and I'm going to work towards that."

Britain's youngest team member, 16-year-old Lizzie Simmonds of Lincoln Vulcans, showed no fear as she progressed through the morning heats of the 200m backstroke and then surprised herself to make tomorrow's final at her first World Championships.

Going in the first of the semi-finals, Simmonds set a new personal best of 2:11.20, taking over a second off her previous best, to qualify in eighth place.

"I didn't expect to make the final so to get in there is amazing," said Simmonds.

"I've really enjoyed the experience so far and I'm now looking forward to living my first World Championship final."