LYNSEY SHARP was the surprise package of Scottish athletics last year.

She won the Olympic 800 metres trial but had achieved only the Olympic B standard. Her nomination for London ahead of four women with the A standard caused uproar. It meant only one woman could be chosen in this event for Britain, an unprecedented decision which provoked appeals, legal challenges, and a battery of bitchy comments on social media sites from disgruntled rivals.

Despite the pressure, the Edinburgh law graduate won European Championship silver and then defied a red-hot draw to reach the Olympic semi-final. Yet now she faces an intense test of diplomacy. Sharp is running for Britain today at the Penn relay meeting in the US. The squad includes two of her disaffected tormentors, Jemma Simpson and Marilyn Okoro.

The US event (19,000 athletes and 115,000 spectators over three days) is steeped in history. The inaugural men's 4 x 110 yards and 4 x 440 yards world records were set here, but this year the University of Pennsylvania meeting is staging a women's 4 x 800m relay for the first time since it was founded in 1895.

It is recent history that concerns Sharp, however. She's sharing a room with Simpson who attempted to orchestrate the campaign against her selection last year, and though Sharp achieved the Glasgow 2014 qualifying standard last weekend, for the third time since the Olympics she was beaten by Okoro in California.

Okoro wears socks embroidered with the slogan "catch me if you can" and tweeted that she was quitting after the selection row. Sharp, however, trounced Simpson in the European final, and in her only other match-up.

So has the atmosphere in their shared room been frosty? "Well . . . " Sharp hesitates, "not too bad. I'm aware of the fact we are in the same British relay team and don't want it to impact on that. There's no residual atmosphere with Marilyn. I actually got on really well with her. I could carry it on and be bitter but it's not my problem.

"It's theirs. She's never going to be my best friend but instead of there being an extra atmosphere, I might as well try to be civil. I don't feel I have something to prove. Marilyn wasn't far ahead of me last week. It will be an interesting season. We're going race each other quite a few times."

The team are chasing a UK record (8min 19.9sec) today that has stood for 21 years. It is made up of Sharp (best time: 2:00.52), Simpson (1:58.74), Okoro (1:58.45) and Tara Bird (2:02.54). Sharp believes the record is easily achievable.

"It's going to be quick. The line-up includes the US, Australia, Canada, Ethiopia, Kenya, Morocco and Russia. But there's no individual pressure," she insists. And so Sharp plans to attack a deficiency: a reluctance to hurt herself on the opening lap, which was again evident last week.

"I stayed back, which is exactly what my coach told me not to do," she said. "I have to push myself harder on that first lap. I'm not going to run faster if I keep going out in 60 seconds. This weekend I can think about the team, rather than how I feel.

"I went out in 58 seconds last summer, but didn't have the fitness because of an injury in January. So it didn't work. I got away with sprinting from 150m to go. But you can't get away with that in really class company.

"My second lap last week was fastest in the field but the first was almost the slowest. I have to work on that. It's good to get the Commonwealth time out of the way, but I expect to go much faster, and know I will. I need 2:00.00 for the World Championships in Moscow. That's the main target this year. I have a race in San Diego next weekend, and then probably the Loughborough International for Scotland next month."

There are no "Olympic scars," Sharp insists. "I don't feel I have something to prove. I'd rather focus on moving forward. I'm concentrating on what lies ahead – the Worlds this year, the Commonwealths and Europeans in 2014."

Sharp's mother, the former Carol Lightfoot, and her father, Cameron, were in the 1982 Commonwealth Games team. "It will be cool to be part of a Scotland team in Glasgow, especially seeing the city interested in a sport other than football," she says.

After graduating last year, she realised she could go anywhere. "I wanted a full-time approach and a group training regularly at the same level as myself," the 22-year-old explains. "I was considering a move [from coach Dave Sunderland] to Terence Mahon in California before it was announced he was coming here with two leading US athletes. It was the perfect opportunity."

Scotland's Eilidh Child is also at the Penn meeting, teaming up with Shana Cox, Christine Ohuruogu and Perri Shakes-Drayton. The European indoor gold-medal 4 x 400m quartet will be bidding for a first podium finish for the UK.

Elsewhere, Chris O'Hare will run the 1500m at the Payton Jordan Cardinal invitation meeting tomorrow at Stanford University in California. It will be the Scot's first outdoor tilt at the distance this year, and a first chance to post a 2014 qualifying time. O'Hare headed the UK indoor rankings with 3:37.25 and ran his outdoor personal best of 3:37.95 at this track a year ago.

Like Sharp, however, his ambitions are higher: a place in Moscow, for which the GB standard is 3:35.00. Three UK men clocked 3.35.19 or faster last year, so the Edinburgh AC man should bet on needing the A standard.