In a few days I am due to attend an interview for a management position which is a step up in my responsibilities but considered *well within my capabilities* by my current leadership team.

One half of the interview team is a Senior Manager whom I have an excellent relationship with and the other half was due to be another Senior Manager whom I had never met. Due to a location change the unnamed Senior Manager has been replaced with a Technical IT Manager with considerably more experience than I have in the advertised role. 

My concern is that the Technical Manager and I went head to head with alternative policy papers in our workplace and despite being junior in experience my policy was picked and implemented by senior management and stakeholders. 

I am now worried that he will attempt to pull out my lack of experience in the interview as a rebuttal to our professional disagreement. 

Are there any concrete techniques I can use to steady my nerves and my answers during the interview? 

The role is Agile Manager (my first). He is an alumni of Nokia, Apple and Reuters as an Agile Technical Lead and currently serves as the Agile Project Manager for the company's most prestigious project.