Australian motor racing broadcaster Leigh Diffey will make his NASCAR Cup race commentary debut at this weekend’s Watkins Glen 355.

The former Supercars commentator will take the lead commentary role at American broadcaster NBC for the first time at the New York state venue and the following Michigan Pure 400 next weekend.

Diffey, who fronts the commentary for Formula 1 and IndyCar at NBC, has previously commentated practice and qualifying sessions but has never called a Cup race.

The station’s regular lead NASCAR broadcaster Rick Allen is covering the World Athletics Championships in London.

“Big picture wise it is not going to change my career as I’m on a solid path with IndyCar and Formula 1, but it is a lovely opportunity,” Diffey told Speedafe.com.

“I’ve called a few Xfinity races over the years but to call Cup is a huge honour.

“As Aussies we have had a smattering of appearances notably Marcos Ambrose and now there is a couple of Aussies at Furniture Row Racing, it is good.

“To be involved in NASCAR at its highest level is pretty cool.”

Diffey is not the only Aussie breaking new ground in the series this weekend.

Former Supercars engineer James Small has been promoted to the role of crew chief on the #77 Furniture Row Toyota driven by Erik Jones.

The 34-year-old Australian, who previously worked for Prodrive, has been handed the opportunity after the team’s crew chief Chris Gayle received a two race suspension for a technical infringement from NASCAR.

Small is joined by fellow countryman and former Kelly Racing engineer Peter Craik at the team.

The Supercars presence will continue with current championship leader Scott McLaughlin due to attend the event.

The DJR Team Penske driver has previously expressed a desire to compete in the category once he has achieved his Supercars career goals.

Diffey, who continues to keep a close eye on Supercars, is confident several of the current field, including McLaughlin, have the ability to follow former champion Marcos Ambrose and break into NASCAR.

Ambrose left Australia for a career in NASCAR at the end of 2005 before returning to his homeland at the end of 2014.

“There are numerous guys that can do it, Scotty and Jamie Whincup could do it. The Supercars field in Australia has always been incredible,” he added.

“I don’t think it is got anything to do with skill as to why there hasn’t been more Australians and Kiwis break into NASCAR, it is the financial model, the opportunity and the philosophy of the team owners.

“There are so many mitigating factors.

“To come back to Marcos’ (Ambrose) example they way he grounded it out to make it to Cup was amazing. It was a huge effort.

“If guys like Scott want to do it then firstly a manufacturer will need to be a big point of assistance and that can help break down a lot of the fences.

“For what Scott’s done already Roger Penske is already a fan of McLaughlin.”

Get the latest NASCAR news, stats, and US racing coverage at Speedcafe US