It has been five years since Bolt set the 100m world record of 9.58 seconds and the 200m best of 19.19 at the Berlin world championships, and this season began late for him as he recovered from minor foot surgery and a hamstring injury.
The lanky Jamaican missed nine weeks of training after having surgery on his left foot in March but shrugged off any suggestion that he might be past his best as prepares for the sprint relay at the Commonwealth Games in Glasgow next month.
"Personally I don't think so," Bolt, 27, told Reuters at his training base in Kingston when asked if his fastest times were now behind him.
Usain Bolt fit and ready for Glasgow Games
"It's all about just being dedicated. Every year I've been injured at some part of the season, so the key thing is try to stay injury-free, try to be more focused on track and field and not be distracted by other things.
"Try to cut down a little on the sponsor-duty things and stuff like that for the upcoming season, try to limit it as much as possible. Then I can put in a lot more work and I'll have more time to work and stay fit and to be focused."
Coach Mills, who has guided Bolt to his six Olympic golds and a record 10 world championships medals since 2007, also believes the sprinter is capable of running faster.
"I wouldn't say that we have seen the best of him," Mills told Reuters after putting Bolt through a sprint workout. "I think that he's capable of more (speed), if he has (injury) uninterrupted preparation."
Bolt appeared to rule out the chance of a mouth-watering duel this year with in-form American Justin Gatlin.
"I don't think the clash will happen," Bolt said. "I'm just coming back, so I'm just trying to get myself into shape and run a few races, just for the fans."
U.S. world silver medalist Gatlin, who is undefeated this year, owns the season's best 100m in 9.80 seconds and has also clocked a world-leading 19.68 seconds for the 200m.
"I don't really worry, I guess he's doing his thing," said Bolt. "I'm just trying to get back and focus on what I need to get done for this season, and then just look forward to next season."
Bolt is scheduled to leave Jamaica on Friday to begin his injury-shortened season at the Commonwealth Games with the 4x100m relay set for Aug. 1 in Glasgow. He has then penciled in four 100m races over the next six weeks.
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