A pair of defective Nikes might have cost a Kenyan marathoner a chance at a world record.

In the Berlin Marathon, Eliud Kiphoge ran into an issue early on as the insoles in his Nikes came loose. ESPN reports the problem occurred during the first kilometer of Kiphoge’s run and around the 20k mark, the insoles of his Nikes were clearly visible. Despite the problem, Kiphoge would go on to win the marathon with a personal-best time of 2 hours, 4 minutes, 63 seconds shy of the world record currently held by Dennis Kimetto.

After the race, Kiphoge acknowledged the problem with the shoe stating, “From the first kilometer, I had problems with my shoes” and communicated that he could’ve run faster. Still, Kiphoge had nothing but positive things to say about the sneaker stating, “I tested the shoe, I tested many pairs of Nike. I think this shoe is the best shoe ever. The shoe is good. The sole was not glued. I used the same pair in Kenya and it was good.” The issue seems to be an isolated incident, but unfortunately for Kiphoge, it happened to occur during competition.

This isn’t the first time Nike products have failed during athletic competition. Most recently, the Spurs’ Manu Ginobili’s Nike Air Max Closer IV came apart during a game back in February while a sole on the 76ers’ Tony Wroten’s Air Jordan Xs came off during a game in March.

[via Complex]