Since bursting on to the sprint scene last season by running 100m in under 10 seconds, James Dasaolu has felt obliged to rebuff the suggestion that physical frailty poses the biggest obstacle to him shining on the world stage.
But after the Sainsbury's Indoor Grand Prix here yesterday, question marks remain as Dasaolu limped over the line clutching his left hamstring, casting doubt on his participation at next month's World Indoors in Poland, where he is Britain's best bet to win gold.
The fact that he beat a world-class field in the 60 metres that included the Jamaican Nesta Carter, the fifth fastest man of all time over 100m, mattered little.
In the heats at the National Indoor Arena, he comfortably won in 6.47sec, a personal best and the fastest time in the world this year.
Come the final, he moved into the lead but 10 metres from the line started grimacing and clutching the back of his leg as he hobbled to the finish, winning in 6.50sec. The early diagnosis is a suspected thigh strain and he will undergo further treatment tomorrow.
Regardless of Dasaolu's availability, Dwain Chambers looks on course to book his place in Sopot when the team to travel to Poland is announced on Tuesday after finishing fourth behind Dasaolu, Carter and Kim Collins.
"It's the second fastest time I've run in his three years," he said of his 6.56sec. "It shows I'm still there. I want to be in the team.
He advised his British rival Desaolu to sit out the Worlds if there was any risk to the rest of his 2014 season. He added: "It's a long season and to get ready for Poland at the jeopardy of ruining his season, I would advise him to sit it out. He's in good shape and the long term should be his main objective."
Ethiopia's Genzebe Dibaba rounded off the meeting with a remarkable third indoor world record in two weeks and a cheque for $15,000 (£9,000) for her efforts as she smashed Sally Kipyego's previous women's two-mile mark by 20 seconds in 9min 00.48sec.
The other international star turns proved a little disappointing. Shelly-Ann Fraser-Pryce, the three-time world champion, was pipped in the women's 60m by Murielle Ahouré while fellow world champion David Oliver did not even make the final of the men's 60m hurdles.
Greg Rutherford fared rather better in his first long jump competition since the world championships in August, equalling his personal best of 8.00m to finish third. After showing no sign of the hamstring tear that caused him to miss the indoor meeting in Glasgow last month, the Olympic champion said: "I was always worried after last year's injury whether I'd make an impact again in my career. That's my best ever indoor competition and my best start to any indoor season."
The 27-year-old said he had no plans to travel to the World Indoors and will instead head to San Diego to prepare for the Commonwealth Games, his season's goal.
Holly Bleasdale had what she called "a bad day" but continued her solid start to the season, winning the women's pole vault with 4.71m as the expected threat from Yarisley Silva, the Cuban Olympic silver medallist, failed to materialise.
Bleasdale said: "If I can jump 4.71m on a bad day then I know the 4.80s and 4.90s will come. But I don't want to peak too soon. At the Worlds is where I want to jump highest and where I want to win a medal."
Britain's middle-distance runners provided the cheer. First Laura Muir held off a world-class field, including the world indoor 3,000m champion Hellen Obiri, to win the women's 1500m in 4:05.32, slashing seven seconds off her personal best, while Andrew Osagie's time of 1:45.22 was just 0.25sec off Sebastian Coe's British men's indoor 800m record.
Lavillenie sets vault mark
Sergei Bubka watched the Olympic champion Renaud Lavillenie break his 21-year-old pole vault record in the Ukrainian's home city of Donetsk yesterday.
The Frenchman, 27, took a leaf out of Bubka's book by raising the record by just 1cm to 6.16m from the mark that Bubka set indoors in February 1993, clearing the height with his first attempt.
Bubka said: "I'm happy because my job is to help athletes perform. Athletics is my life. I'm pleased for him and for athletics."
When Bubka was setting his 35 world records, there were separate marks for indoors and outdoors. Now world records are accepted whether inside or out. Lavillenie's best leap outdoors is 6.02m.