NICOLA Sanders and her 4x400 metre (m) teammates are Great Britain's best chance of a relay medal at the 2012 London Olympic Games, but only if they can lay a platform for Christine Ohuruogu - according to four-time Olympic champion Michael Johnson.

The 4x400m relay races will be the last on the track at London 2012 so with the individual event - which Windsor, Slough, Eton & Hounslow Athletics Club star Sanders will not be competing in - done and dusted all eyes will be on the British quartet.

By then we will already know if Ohuruogu has successfully defended her Olympic crown while Sanders, a former world silver medallist, will be fresh and raring to get out on track.

And Johnson is confident that with a number of different names to choose from, including Shana Cox, Lee McConnell and hurdler Eilidh Child, team GB could well have something to shout about on Saturday August 11.

"The British women's 4x400m relay is a strong team," said Johnson, who was speaking following the launch of his new mobile phone apps, 'Michael Johnson's Motiv8' and Michael Johnson's 'Fun Run', which are aimed at the health and fitness market.

"Of the relay races in London I'd have to say this is Britain's best chance of a medal if they can all perform at their best.

"They've got a strong combination of youth and experience in that team, the older wiser heads who've been there and done it all before, girls like Nicola and Lee McConnell have run plenty of relays before.

"And then of course you've got Christine, that's a big plus. The team know she will be a potential medallist in the individual events, and that will give her and the rest of the team a lot of confidence.

"If you know your job is to just try to keep your anchor leg in contact with the potential medallist then that's a lot easier and then they can leave Christine to do her job and it could be a podium celebration for them." Johnson's crowning glory came in Atlanta in 1996 when in front of a home crowd he stormed to gold in both the 400m and 200m, a double that has never been accomplished before or since at the Games.

And the 44 year old, whose world record for the 400m set in Seville in 1999 still stands to this day, has called on the Brits to make the most of the home support as he did 16 years ago.

"I think the biggest advantage of being at home is in the lead up to the games," he said.

"The British athletes are trying to be at their best every day so they can be at their best at the Olympics - it's the pinnacle for them.

"They are reminded every single day because of the build-up to the Games that's been going on for the last few years, of what they're training for.

"Every day you're not going to be motivated 100%. It's great motivation if you're not feeling quite right, when you see an Olympic billboard reminding you of what's coming, that it's a great opportunity you have - I had that in 1996 at Atlanta.

"For some athletes it may actually be more pressure than they can handle at a home Games. For me it was great having that American crowd." Get your fitness back on track and teach your kids the importance of healthy eating with Michael Johnson's Motiv8 itunes.apple.com/gb/app/michael-johnson-motiv8/id501945154?mt=8 and Michael Johnson's Fun Run itunes.apple.com/gb/app/michael-johnsons-fun-run/id536103489?mt=8. Available to download now from the iTunes App Store ** SEE Friday's Observer for all the latest 2012 London Olympic Games news ** ** Follow the Observer on Twitter @Observer_sports **