Dame Kelly Holmes, the double Olympic champion, has still not decided whether to compete in next month's European Indoor Championships in Madrid.
Holmes has spent two weeks training in the warmth of South Africa and will race tonight at the Norwich Union Grand Prix in Birmingham.
But the 34-year-old, winner over 1,500 metres at the Norwich Union international meeting in Glasgow, has yet to confirm her place for the showcase in Spain starting on March 4.
"I haven't even thought about," said Holmes, a day after she was involved in the International Olympic Committee's visit to assess the London 2012 bid.
"Today the answer would be no - let's see how it goes and what happens tomorrow."
She will test her form over 1,000m at the National Indoor Arena tonight.
"It's going to be a tough race," said Holmes, who in last year's meeting set a UK national record of two minutes 32.96 seconds when beating Jennifer Toomey.
Toomey is again in the field, along with Namibia star Agnes Samaria and world indoor 800m bronze-medallist Jo Fenn.
Holmes played down the furore of missing last weekend's European trials and AAA Championships, which led to a fine, confirming again the meeting never figured in her programme.
"I never had Sheffield in my plans," said the 800m and 1,500m Athens Olympic champion. "I needed two weeks' training to prepare for Birmingham and Glasgow, and they were the only two races ever in my schedule." Birchfield Harrier Nathan Morgan has been forced to pull out of his long jump showdown with Chris Tomlinson, with a recurrence of a heel injury that flared up during the AAA Trials at Sheffield last weekend.
Genuine world record attempts can be expected from overseas visitors in the men's 1,500m, women's 3,000m and pole vault.
Kenya's Bernard Lagat could target Hicham El Guerrouj's eight-year-old metric mile record of 3.31:18, while Ehtiopia's Olympic 5,000m gold medallist Meseret Defar looks a good bet to beat Berhane Adere's three kilometres time of 8.29:15.
Jo Pavey is looking to better the 8.34:55 she managed last year when she narrowly broke Liz McColgan's UK record.
Pole-vaulter Yelena Isinbayeva, who set a world record of 4.87 in Donetsk last week, looks certain to go even higher.