British Athletics has named a 35-strong team for next month's World Indoor Championships in Poland, but one of the strongest hopes for a gold medal is missing.
Sprinter James Dasaolu is ranked number one in the world in the 60 metres this year after posting a personal best of 6.47 seconds in the semi-finals of the Sainsbury's Indoor Grand Prix in Birmingham on Saturday.
He won the final, too, but crossed the line clutching his left hamstring and a scan has shown a minor tear, which rules him out of the championships in Sopot from March 7-9.
Dasaolu, who won a silver medal at the European Indoors last year, will resume training shortly in preparation for the outdoor season.
He said: "Unfortunately it will keep me out of competing at the World Indoors.
"I am disappointed but this is going to be a big year and I don't want to take any risk at all. I will now concentrate on being 100 per cent fit for the outdoor competitions."
It is the latest injury setback for the 26-year-old, who made headlines last summer by running 9.91secs for the 100m, the second fastest time ever for a British athlete behind Linford Christie.
There was also disappointment for multi-eventer Katarina Johnson-Thompson, who had hoped to be given an invitation by the IAAF for the pentathlon.
The 21-year-old has been in superb form this season but was forced out of her qualifying event for the championships at the weekend because of illness.
That left her relying on the one invitational spot, given at the discretion of the world governing body, but it was confirmed on Tuesday that she has missed out.
Johnson-Thompson will instead compete in the long jump, where she should be a medal hope having set a new personal best of 6.75 metres at the national indoor championships, the third longest jump in the world this year.
At the same meeting, Johnson-Thompson broke the British high jump record with a leap of 1.96m.
Laura Muir will be Britain's main hope for a gold medal as the top-ranked woman in the 800m this year, while pole vaulters Holly Bleasdale and Luke Cutts are both second.
Asha Philip is also ranked world number two in the 60m and will be joined by 19-year-old Sophie Papps, who makes her senior debut for Britain.
In the absence of Dasaolu, former world indoor champion Dwain Chambers and Richard Kilty will compete in the men's 60m.
British Athletics performance director Neil Black said: "This is a relatively young team with a number of new faces taking individual places, which is encouraging as we focus on long-term development towards 2016 and 2017.
"Where there were any close decisions, we have prioritised the Sainsbury's British Athletics Championships results, and it is good to see athletes and their coaches who have made significant breakthroughs in the last year are maintaining those results."