PR1/Mathiasen Motorsports is an American sports car racing team that currently competes in the LMP2 class of the WeatherTech SportsCar Championship.

The IMSA SportsCar Championship, currently known as the IMSA WeatherTech SportsCar Championship under sponsorship, is a sports car racing series based in the United States and Canada and organized by the International Motor Sports Association (IMSA). It is a result of a merger between two existing North American sports car racing series, the American Le Mans Series and Rolex Sports Car Series. At its inception, the name was United SportsCar Championship, which subsequently changed to IMSA SportsCar Championship in 2016. Rolex SA's Tudor brand was the championship's title sponsor in 2014 and 2015, and since 2016 WeatherTech has served as title sponsor.