Sinnema began his work as an assistant during the 2015 season at Dordt. Prior to coming to becoming the pitching coach at Dordt, Sinnema served as the head coach at West Sioux High School in 2011, and as a volunteer assistant coach for the Gallatin Valley Outlaws in 2013. In addition to his coaching duties with the Defenders, Sinnema has managed the Larchwood Diamonds of the South Dakota Amateur League in 2017 and is currently serving as the head coach at Western Christian High School in Hull. He has also coached several seasons of high school basketball and golf at Manhattan Christian High School (Montana), and assisted with youth baseball teams in the area.
Patrick Sinnema graduated from Dordt University in 2011 and played four seasons for the Defenders baseball program, primarily as a pitcher. He finished his four years as the career leader in innings pitched, third in wins, and fifth in strikeouts. He earned all-conference recognition in 2010 and 2011. Sinnema still competes during the summer months, playing with the Larchwood Diamonds in the South Dakota Amateur League, where he was part of the state runner-up team in 2017.
B.A. HPER - Exercise Science and Recreation Management, Dordt University (formerly known as Dordt College), 2011