Beal was born in Godstone, Surrey. He played for Surrey boys and England Youth before signing as an amateur for Tottenham Hotspur in 1960 and became a professional at the club in 1962.
He made his debut as a defender against Aston Villa in 1963, and went on to make 16 appearances in that season.
By the start of the following season Danny Blanchflower had retired with Beal taking on the former captain's right half position. With the team in transition, he only made eight appearances that season.
The versatile player filled a variety of defensive positions and featured in 21 matches in 1965–66, started in 26 games in 1966–67, but did not feature in the 1967 FA Cup Final because of an injury. By the late 1960s he had fully established himself in the side and consistently showed his calm, authoritative and composed style.
Beal attempts to make a goal-line clearance which leads to the first goal by Feyenoord in the second leg of the 1974 UEFA Cup final