Alexander George Karras (born July 15, 1935, in Gary, Indiana, United States), nicknamed "The Mad Duck", is a former football player, professional wrestler, and actor who is best known for playing with the Detroit Lions from 1958-1962 and 1964-1970. In addition, he starred on the ABC sitcom Webster, alongside real-life wife Susan Clark, as the titular character's adoptive father.

Alex Karras is the son of Dr. George Karras, a Greek immigrant who graduated from the University of Chicago and got his medical degree in Canada. There, George Karras met and married a Canadian woman, Alex's mother. George Karras opened a medical practice in Gary, Indiana, but he died when Alex was 13 years old. By that time, Alex Karras had learned to play football in a parking lot near his home, and he blossomed into a four-time Indiana all-state selection at Gary Emerson High School.

His older brothers, Lou (a future member of the Redskins) and Ted (who later played with the Bears and Lions), had played at Purdue but later Ted transferred to Indiana. Because of this, Alex said, "Indiana had the inside track" on recruiting him, but shortly after he graduated high school, several coaches from the University of Iowa took Karras up to Spencer, Iowa, and persuaded him to sign with the Hawkeyes. The coaches had taken Karras to secluded Spencer to keep him away from rival recruiters.