Sabastian Sawe, the first man to run the marathon in under two hours, believes even faster times are on the horizon both for him and the sport.
In April, the 31-year-old Kenyan clocked 1:59:30 in London, shattering the two-hour barrier many felt was untouchable.
"I know it's possible to run under 1:59," Sawe told AFP in an interview in Berlin, adding "it is hard to predict how fast I will be, but (it's possible) if we've got nice weather, good pacing and I am in good shape".
Sawe said further records will fall as running's popularity skyrockets and technology improves.
"We don't know about the years in front of us because maybe other people will come along and do something great. There are no limits for now."
'SOMETHING SPECIAL'
Even Sawe was shocked by his exploits in London.
"I was not expecting to run under two hours," he said.
"I wanted to retain my title. When I saw (the time) with my own eyes as I was almost finishing the race, it was something surprising for me, and I was so happy and grateful."
The 2025 Berlin winner was set to run in the German capital again on Sunday, but missed out with a fractured leg.
"It was hard, but I had to accept it because injuries are part of running."
Sawe hopes to return for London in 2027 but has his eye on doing "something special" at the 2028 Los Angeles Olympics.
"Now I'm getting to be someone bigger in athletics, I've learned a lot, and I've learned patience is important and recovery is important to make you feel fast and strong."
Sawe was speaking in Berlin just one day after a brutal injury crushed Tigst Assefa's shot at the women's record.
Cruising on world record pace until the 35-kilometre mark, Assefa ruptured her Achilles tendon.
Running the last two kilometres without an Achilles, the Ethiopian somehow crossed the finish line first, recording the third-best women's mark and a course record before collapsing.
"When I saw what happened, I was shocked because she was running a good race this year in Berlin. Everything was perfect for her... She was running to achieve everything she had worked for."
Sawe backed the 29-year-old Assefa to chase down the world mark.
"For sure she will because Tigst is a very strong woman and her mentality is something else. She always has the courage to push her limits. She's always been a winner."
'PROTECTING SPORTS'
The brutal injury not only snatched Assefa's shot at history; it stole a chance to overcome a record many believe is tainted.
Assefa's 2:11:04 was just over a minute behind the 2:09:56 set by Kenyan Ruth Chepngetich in 2024.
A year later, Chepngetich was suspended for three years for doping, but her record still stands.
Sawe has done more than most to improve perceptions, particularly in Kenya where more than 100 athletes are currently suspended.
For years, Sawe has taken the unusual step of volunteering for extensive additional testing, averaging an additional test every three days on top of national and international requirements.
"Even with what I have achieved, I want to show the world that not all athletes are running dirty... there was a time where there was more doubt than belief.
"It's a nice routine for athletes to have multiple tests to prove that they are running clean and winning clean. It shows we are protecting sports for the future."
In September, Nairobi was announced as the first African host of the World Athletics Championships, with the Kenyan capital due to host in 2029.
Sawe said he hoped his testing regime would help "give a good reputation to my country and show we are fighting doping in many ways".
"It's something special to us Kenyans. It's an important moment to have it in our country and we appreciate it so much."