Wilfred Charles Siebert (born January 14 1937 in St. Mary, Missouri) is a former Major League Baseball pitcher from 1964 to 1975. He finished with a record of 140-114 and a 3.21 ERA. He threw a no-hitter on June 10, 1966 against the Washington Senators. He was originally drafted simultaneously by the Cleveland Indians and the St. Louis Hawks of the NBA.
Siebert attended the University of Missouri and played on the 1958 team that lost in the College World Series finals in 12 innings. He was selected to the CWS All Tournament Team that year.
Siebert is the last American League pitcher to hit two home runs in one game, accomplishing the feat as a member of the Boston Red Sox on September 2 1971 against the Baltimore Orioles.