Sportswear giant Nike will invest US$13.5m (£9.3m, €12.4m) to renovate the track and field facilities at the University of Oregon – one of the venues earmarked for the 2021 Athletics Championships.

Oregon-based Nike will grant two instalments of US$6.75m (£4.6m, €6.2m) to the University of Oregon Foundation to upgrade the institution’s Hayward Field from a 10,500-capacity ground to a stadium that can hold 30,000 spectators with temporary seating.

The first instalment has already been granted, with the second dependent on further fundraising. Construction is due to begin in August and the improvements are expected to be completed to host the National Collegiate Athletic Association (NCAA) Track and Field Championships in 2017.

Nike maintained that it was “not party to the bid or the decision to award 2021 to Eugene”.

“We have always been an avid support of track and field and believe that the 2021 World Athletics Championships taking part in the USA, for the first time ever, is a positive step for the sport’s continued growth,” said Nike in a statement.

The town was awarded the competition in April last year, but French authorities have since opened an investigation into the decision-making process of the International Association of Athletics Federation (IAAF).

Last year, it was alleged that IAAF president Sebastian Coe liaised with Nike executives via emails appearing to discuss Eugene’s bid for the championships. The town had previously bid for the 2019 World Athletics Championships, but lost out to Doha, Qatar.

According to reports an IAAF spokesperson said Eugene’s proposal already stated that the “stadium development was going ahead whether 2019 or 2021 was successful”.