Peter Gerard Richert (born October 29, 1939 in Floral Park, New York) is a former Major League Baseball left-handed pitcher. He pitched for the Los Angeles Dodgers (1962–64, 1972–73), Washington Senators (1965–67), Baltimore Orioles (1967–71), St. Louis Cardinals (1974) and Philadelphia Phillies (1974).

In his Major league debut on April 12, 1962 against the Cincinnati Reds at Dodger Stadium, Richert set a record by striking out the first six batters he faced. His Dodgers trailing 4-0, he entered the game with two outs in the top of the second inning and struck out Vada Pinson for the final out. Richert then recorded a four-strikeout third inning in which his victims were Frank Robinson (his future Oriole teammate), Gordy Coleman (who reached first base on a passed ball by Johnny Roseboro), Wally Post and Johnny Edwards; his record-tying sixth strikeout was of Tommy Harper leading off the fourth. To date, Richert is the only pitcher to record a four-strikeout inning in his Major League debut. Richert won the game in 3⅓ innings of relief, giving up no hits or walks and striking out seven. That year, he went 5-4 as a spot starter in a rotation led by the future Hall-of-Fame duo of Don Drysdale and Sandy Koufax. In 1963 he went 5-3 on a Dodger team that won the World Series; Richert did not pitch in the Series, which the Dodgers swept from the New York Yankees.