Brian Matthew Duensing (born February 22, 1983 in Marysville, Kansas) is a major league baseball starting pitcher for the Minnesota Twins.

He was born in 1983, the same year as his teammate, catcher Joe Mauer.

Duensing went to Millard South High School in Omaha, Nebraska, where he earned second-team all-state honors in both his junior and senior years. His senior year he batted .429, and went 2-2 with a 3.78 earned run average on the mound. His combined record in two seasons of American Legion ball was 16-3 with 141 strikeouts. He had a 0.74 ERA, and a .522 batting average his second season.