Athletics/Great Ireland Run:Sonia O'Sullivan could recall maybe a dozen rivals over the course of her great career and it's fitting that the one joining her in Sunday's Great Ireland Run is Ethiopia's Derartu Tulu.

This is the race marking the start of O'Sullivan's final lap as an international athlete, and although the finish line isn't yet entirely in sight, it's an occasion that deserves to be both honoured and celebrated.

Tulu's presence in the Phoenix Park on Sunday will go some way towards honouring O'Sullivan, as no less than the Cork athlete, she is unquestionably one of the greatest distance runners of her generation. Now aged 36 - one year younger than O'Sullivan - she became the first Ethiopian woman to win Olympic gold when taking the 10,000 metres in Barcelona in 1992. After finishing fourth in 1996, Tulu regained the title in Sydney, with O'Sullivan finishing sixth having won silver in the 5,000 metres.

Organisers of Sunday's race have gone to some lengths to give O'Sullivan a celebratory farewell, even if there's a small chance she'll be back again next year to complete her final lap.

Several busloads of supporters will travel from Cork, with former school-mates, coaches and other rival athletes among the invited guests.

Ideally O'Sullivan would win the 10km event, although that can't be fixed as easily. Like Tulu she is naturally past her prime at this point, and a winning time of under 33 minutes is expected - which is probably just outside O'Sullivan's range. The more likely challengers include the Moroccan-born Fatiha Baouf of Belgium, Helen Clitheroe of Britain, the rising Australian star Victoria Mitchell, and Allesandra Auguilar of Spain.

Of course the event is largely a fun run anyway, with the 9,000 entries - most of whom will be glad just to get around the Phoenix Park - up almost 20 per cent on last year.

O'Sullivan, however, has been training consistently well during the winter in Australia, even clocking some decent times on the track, and she definitely won't be shying away from the leaders.

"We do expect this race to be won in around 32, 33 minutes," explained the elite-entry director, Matthew Turnbull. "I'm not quite sure if Sonia is still up to that standard, but she won't be too far off. And the same with Derartu Tulu.

"Given her rivalry with Sonia over the years we're obviously delighted she's here to compete with her, although she is just coming off the birth of a child late last year, and she's not 100 per cent sure herself how fit she is."

The men's race looks even more competitive, thanks mainly to the presence of the powerful Australian Craig "Buster" Mottram.

Starting the race at 1pm on Sunday will be An Taoiseach Bertie Ahern, but after that it's all eyes on O'Sullivan. No one really expects this to be her last race in Ireland, but when she does eventually retire we'll certainly never see her likes again, and for that reason alone it's a race well worth watching (it is also live on RTÉ Two television, by the way.)