It is particularly so when the fighter in question is his daughter Katie Taylor, widely regarded as the greatest women boxer in the history of the sport.
As her father and her coach, Peter admits it is sometimes tough to combine both roles and remain dispassionate.
He said: “What I always say is that I’m her father first and her coach second – every time. It is difficult to remain detached. I get as nervous as she does before every fight.
“Every punch she takes, even in sparring, I feel the pain. It’s difficult to watch it at times but I have to remember I am her coach. Fathers tend to be protective of their daughters and keep them from harm but this is the sport she has taken and I’m very proud of her.”
As one of the ambassadors for the Baku 2015 European Games, Katie is one of its highest profile competitors, but has shunned the limelight in the build-up to her lightweight competition which begins on Sunday 21 June at Crystal Hall.
Peter said: “It’s like that at all tournaments. She is well-known but she likes to keep a low profile and concentrate on her boxing.”
The five-time world champion and London 2012 gold medallist is keen to add the European Games title to her medal haul.
Peter said: “She just wants to keep on winning championships and this one is important because it’s the first European Games. After that it will be the Rio Olympics. She never gets tired of winning. She wants to be known as the greatest women boxer of all time.”