Iconic commentator Leigh Diffey is set to call his last IndyCar race this weekend.

The forthcoming double-header at Iowa Speedway will be the last event Diffey attends before turning his attention to the Olympic Games in Paris for NBC.

Although the Olympic Games finish before the IndyCar season concludes, it’s expected Diffey will not return to the commentary booth after Iowa.

That will end a 12-year spell calling IndyCar races which began in 2012.

Diffey has called the last six Indianapolis 500 races and has become an iconic voice associated with the modern era of IndyCar.

A change of broadcast rights in the United States will see NBC relinquish the reins and Fox Sports take over in 2025.

With Diffey tied to NBC, he will not be part of Fox Sports’ coverage next year.

Fox Sports has not yet confirmed who will lead its commentary team under the new deal.

Observant IndyCar fans will have already noticed a shift in the NBC commentary team lately.

Diffey was absent for the most recent Mid-Ohio race, which was called by Kevin Lee alongside Townsend Bell and James Hinchcliffe.

Charlie Kimball also joined the broadcast team as a pit reporter at Mid-Ohio with Georgia Henneberry.

This weekend’s Iowa double-header will be called by Diffey, Bell, and Hinchcliffe. Lee will move to pit reporting with Henneberry and Dillon Welch.

Although this weekend will be Diffey’s last with IndyCar, it’s expected the Queenslander will land another role in motorsport commentary.

Earlier this year, United States outlet Sports Business Journal tipped Diffey to join NBC’s coverage of the NASCAR Cup Series following the Olympic Games.