The loss of former champion Paula Radcliffe due to tonsillitis for Sunday's IAAF World Half-Marathon Championships, in Birmingham, has dominated the athletics headlines this week.

But one spin-off from that has been Claire Hallissey's promotion to Great Britain's No 1 runner.

"No pressure at all then!" said the Bristol & West AC runner, taking a break from writing her PhD at Bristol University.

"Losing Paula is a shame for the British women's team, but in some ways it takes the pressure off the rest of us. I'm looking forward to the race, but also feeling a bit nervous."

That's understandable as Hallissey, who booked her place in the team by winning the trials event that was incorporated into the Bristol Half Marathon last month, will be running the biggest race of her career to date.

Strong teams from Africa, Japan, Europe and America means that Sunday's race, which is being shown live on Sky Sports, is a big step up from the European Cup 10,000 metres in June, when Hallissey made her British debut.

"It's probably a surprise that I made my international debut on the track first before the road and, hopefully, I can do it in cross country this winter as well," added Hallissey.

As for Sunday's race, Hallissey has to set her sights considerably lower than Radcliffe, who first won this title in Bristol eight years ago and repeated that triumph in Portugal in 2003. Hallissey has made fantastic progress over the past year, but is not at that level yet, though that's not to say she is not ambitious.

"Position-wise, it is hard to predict until you see who turns up for the race," explained Hallissey. "But if I look at the time I want to run, then breaking 72 minutes, which I just missed at Bristol (72:03), would be nice – plus finishing first British runner.

"Whether I can knock off another minute and run sub-71 minutes may be pushing it a bit, so we'll see what happens."

Looking at previous results, if Hallissey achieves her target of running under 72 minutes, she would have finished 11th in Rio de Janeiro last year, 14th in the 2005 race in Edmonton and ninth in New Dehli five years ago.

Going back to the Bristol race in 2001, 72 minutes would have secured her 26th place, so clearly on past performances, plus the ability to raise her game for the big occasion, a top-20 finish is within her reach.

● Westbury Harriers send a strong women's squad to the opening Gwent Cross Country League race at Newbridge Fields, Bridgend, on Sunday (12.35pm).

In-form Emma D'Alton will be joined by Sophie Voller, Debbie Marsden, Lizzy Smith, Wendy Tippett, Lynne Gallagher, Pat Gallagher, Debbie Cleary, Heather Stacey, Gill Jones and Hayley Johnson. Team spokeswoman Tamsin Chick said: "We have a really strong squad, with great depth in numbers, so should do well as all the girls are pretty fit at the moment." Bristol & West AC's Robbie Bugden makes his comeback after his commitments with the RAF saw him out of competitive action for the past year.

But he has been training consistently, so will be looking for a decent performance, as will Dan Woolford, Sean Hazell and Nathan Young, while in the young athletes races, Hannah Cockram, Zac Tobias, Billie Williams and Olivia Sadler are also running.

● Bitton Road Runners will send strong squads to the opening fixture of the Gloucestershire Cross Country League, staged at the Cotswold Farm Park, near Bourton-on-the-Water, tomorrow.

Dawn White, Martin Stalley, Arwel Roberts, Dave Waters, Helen Hinsley, James Wade, Mark Kingdon and Ron Shannon head to the Cotswolds, with the first race at 12.10pm, the senior women at 2.05pm and senior men 40 minutes later.

● Entries are still being taken for the Mendip Muddle 20k multi-terrain race from the Charterhouse Centre, near Blagdon, on Sunday (11am), but check the website at www.westonac.co.uk for the latest details.

● The Horton Winter Bull 5.2-mile multi-terrain race takes place on Sunday from Horton Village Hall (11am), with entries taken on the day. For further information contact Barbera Denton on 01454 313889.

● In tomorrow's Post, find out who is the 100th winner of the Easy Runner athlete of the month competition, which was launched eight years ago.