Bunta Sugawara seems like the ideal actor for this sort of role, just as Kinji Fukasaku is the ideal director. I often equate the 1970s yakuza films of Japan's Toei studio with the work of Warner Bros. in the 1930s and 1940s, and in that context Sugawara is Toei's Humphrey Bogart (their Cagney being Sonny Chiba) for the brooding, world-weary quality he brings to so many films while remaining capable of fearsome violence. Sugawara was the star of Fukasaku's five-film Battles Without Honor and Humanity series (1973-4), packaged in the U.S. for the DVD market as The Yakuza Papers. Fukasaku plowed straight ahead with more yakuza films, including the classics released here as Cops vs. Thugs and Yakuza Graveyard. But Toei wanted literal sequels to the Battles epic, and Fukasaku obliged with a "New" series of three films in which many of the original cast took on new roles in the same general time period. For some reason, despite the obvious exploitation angle, the "New" trilogy is less widely known in the U.S. A small company called Kurotokagi Gumi has released the first two films, along with many other Toei items, with decent English subtitles, while the larger companies who've released other Fukasakus steered clear. I presume that's because the "New" films are considered inferior work, but the first New Battles film finds Fukasaku and Sugawara near their top form.
You can always depend on Fukasaku for a unique angle on yakuza action
Sugawara plays Makio Miyoshi, who we first see carrying out a bungled hit while disguised as a crippled war veteran. Right away, we're immersed in the familiar maelstrom of Fukasaku's yakuza films as the director films violent action with a handheld camera that seems to be buffeted by the mayhem like a leaf in a storm. He consistently creates the illusion of cinema verite, and the key to that is that he stages chaotic action. His street battles may be elaborately planned, but they lack any glamorizing choreography. Things never seem to happen quite as planned, leaving attackers, victims and bystanders alike confused and panicked. Fukasaku quite deliberately takes the opposite approach from the lethal elegance of the samurai film, but the effect is just as much the product of master craftsmanship as the most stylized sword duels.
Fukasaku doesn't stint on the gunplay and bloodshed this time -- Aoki's last stand is a broad-daylight deathmarch capped by a thunderous reprise of Toshiaki Tsushima's famous Battles fanfare -- but New Battles 1 is in a lower key than its five predecessors overall, more memorable for its subtler details that for its obligatory battles. Fukasaku is quoted on the box cover saying that he meant to take a "deeper look" at his gangsters in the new series. While this opener isn't necessarily superior to the original Battles, I think that he succeeded in his purpose nevertheless.