I haven't really watched sumo all that much lately, but I like to watch a bit now and then. I have noticed that the wrestlers presented in this manga are more or less based on real life wrestlers. As an example, Saganohana in ch.5 is probably based on Yokozuna Takanohana. In this chapter there is no doubt: Tamagoriki is based on Takatoriki.
Takatoriki won a record number of fighting spirit prizes, but never ranked higher than sekiwake. The manga tournament is clearly based on the March 2000 tournament, where Takatoriki was ranked close to the bottom of the division at maegashira 14 and would have been demoted to the Juryo division if he had a losing record. Instead he won his first 12 bouts before losing to Yokozunas Akebono and Musashimaru. Unlike in this manga, he fought back by beating fast-rising Sekiwake Miyabiyama* in the last round, getting his only top division tournament win at 32 years old. The next year he was demoted to Juryo, and retired after a year there.
From what I remember, Takatoriki was always exciting to watch, lots of slaps and agressive pushing. He seemed to be very popular with the Japanese audience.
* In his fight with Takatoriki, Miyabiyama had risen so fast through the ranks since turning pro that he fought as Sekiwake without having a topknot yet. Extremely rare and maybe shocking to some conservative Japanese.