One of these, performed right after stepping into the ring for a match, involves tossing handfuls of salt onto the ground. The salt chases away evil and purifies the ground. The ritual was also a way to ask the gods for protection from injury. Some 45 kg of salt—enough for all of the wrestlers for one day—has been brought to the ring.

Next, the two rikishi go through a series of motions. They slowly lower their hips, clap their hands twice, rub them together, and hold out their arms wide, palms down. This ritual comes from the days when sumo was played outdoors—wrestlers would tear off some weeds and use the dew on them to clean their hands. The hand movements also showed that the wrestlers had no weapons.

Water (mizu) is a very important part of ceremonial sumo. A wooden pail, containing "water of strength"(chikara mizu) is placed outside and below the ring for the wresters to rinse their mouths and symbolically cleanse their bodies. The purple mizu hikimaku curtain suspended from above the ring is associated with the notion of water calming the aggressiveness of the wrestlers. And if the bout drags on too long, the referee will make them take a short break called mizu iri. Thus, salt and water are considered to be charms to protect the wrestlers from harm.

Next, they stride to the center of the ring, lift one leg high, stomp hard, and then do the same with the other leg. This ritual stomping, called shiko, is a basic warm-up exercise and strengthens the lower body. The original purpose is said to have been to crush evil spirits in the ground.

Now they are almost ready for the clash. They crouch down and glare at each other. They are controlling their breathing, expelling air from their lungs, then filling them almost full and holding their breath—they say this is the moment when they have the most power, the ideal condition for storming forward and colliding with one another.

There are 70 categories of moves used to overcome the opponent. One common one is yorikiri (frontal force out, pushing him out of the ring). Another two involve a grip on the opponent's loincloth: these are uwatenage (overarm throw) and shitatenage (underarm throw).

The match is refereed by a gyoji. He stands in the ring with the wrestlers wearing a kimono and an eboshi hat. There are a number of gyoji ranks, each differentiated by the clothing. When a yokozuna—the highest-ranked wrestler—is fighting, the highest-ranked referee, called a tate-gyoji, makes the calls.

During bouts, the gyoji calls out "Hakki yoi!" to spur the wrestlers on. Often, there is an obvious winner. In other cases the gyoji has a hard call to make. For example, sometimes the wrestlers fall out of the ring together, hitting the ground at practically the same instant. This will bring members of the judging committee up to the ring from below, to confer together and decide. In the not-too-rare cases when it is too difficult to name the winner, a rematch is ordered.

After the bout, the two wrestlers bow to each other. Prize money is awarded to winners of matches that have attracted considerable interest. Before taking the prize, the victor jerks his hand downward like a sword three times, symbolizing his thanks to the three gods of victory.

The day's matches are over at about 6 p.m., and end with a final ceremony called yumitori shiki. One wrestler climbs up into the ring and twirls an archer's bow in his hand. This tradition comes from the old practice of giving a bow as a prize.

Sumo is more than wrestling, it is Japan's national sport, combining ceremony and competition. And rikishi do more than just wrestle—they practice and exercise daily, and follow the life of sumo-do, "the way of sumo." Over the last few years, the ranks of sumo wrestlers have been joined by a growing number of non-Japanese (a total of 61 in 2004). A rikishi from Mongolia, who has taken the name Asashoryu, is one of those who now holds the top rank of yokozuna. Ancient sumo traditions are becoming part of the growing movement of globalization.