In 1975, Marvin Jenson received a patent (No. 3,876,197
) for a circular boxing ring. As he noted in his patent, a circular ring is safer than a square one due to the lack of corners:
Many times during a boxing contest one of the contestants will be trapped in a corner and is unable to escape the ensuing onslaught of his opponent. This may result not only in a serious physical injury to the trapped fighter, but also detracts from the art and skills of the sport.
In a newspaper interview, Jenson further explained that the idea for the round boxing ring had occurred to him after watching the 1961 fight between Benny Paret and Emile Griffith
, during which Paret got trapped in a corner and took such a beating that he fell into a coma and died.
Jenson's patent drawing
Jenson's circular ring in use
Jordan Valley Sentinel - June 10, 1976
Jenson was hardly the first person to come up with the idea of a circular boxing ring. The idea has been around for a long time. In fact, way back when fighters used to compete in circles drawn on the ground, which is why boxing rings came to be referred to as 'rings' in the first place, rather than 'squares'.
So how did boxing rings end up being square and continue to be so?
As far as I can tell, it's mostly a matter of convenience. It's easier to string rope in a straight line rather than a circle.
An earlier attempt at a circular ring
Newsweek - May 8, 1944