Jerome "Doc" Louis is an ex-heavyweight boxing champion, and Little Mac's coach. In the Wii title, he is voiced by Riley Inge. He is an overweight African American man who wears a red jacket. He is very engaged in Mac's training and matches. In the NES and Wii installments, Doc trains Little Mac as he fights throughout the World Video Boxing Association circuits. This often includes Mac running behind Doc as he rides his bike, now one of the most iconic features of the Punch-Out!! series. He also invented the Star Punch, Mac's strongest move. He may have been named after the legendary real life boxer Joe Louis.
Formerly a heavyweight boxer, Jerome Louis' presence achieved fame in the United States around 1954. Decades later Doc, now coaching the sport, has a chance encounter with a young fighter named Little Mac, who has aspirations to box professionally. Louis agrees to take charge of Mac, teaching him everything there is to know about boxing. In between rounds, Doc Louis often advises on a weakness or trick in Little Mac's opponent for him to exploit. With the Wii reboot of Punch-Out!!, he also appears to have taken a liking to chocolate bars and uses a lot of bad jokes. In the NES incarnations of Punch-Out!! as well as the 2009 Wii reboot, Doc Louis can often be seen training Little Mac during cinematics. However, it is not until Doc Louis's Punch-Out!! that players can actually train against him as part of gameplay
In between rounds of the Punch-Out!! (Wii), he explains in more detail on an opponent's weaknesses and techniques they use along with making mention on what techniques Mac should use for each opponent and how he should avoid certain attacks. He will also encourage Little Mac into defeating his opponent and at times mock some opponents such as Aran Ryan, but at times may mention trivial information about some boxers like Super Macho Man's fame, fortune and his Hollywood connection. Besides this, he may also talks about random topics like chocolate and Club Nintendo.
In all modes, Doc Louis plays very similarly to some of the opponents in the Wii version of Punch Out!!. He uses every type of punch. In Doc Louis's Punch Out!!, Doc usually says something before he attacks, such as "dodge!" or "duck this one!". Chocolate bars fly off Doc Louis's head if the player manages to stun Doc Louis.
In Sparring Match, he will begin using Star Punches. Before he attempts to hit you with a Star Punch, he gets a star off you by hitting you with a very quick hook (though it can be avoided) and then throwing the Star Punch. His Star Punch instantly takes off all your stamina, resulting in a knockdown. Occasionally, he will take out a chocolate bar. If you hit it out of his hands, he will get enraged and take off his jacket, revealing his jaguar-pattern shirt and shows a very amusing reaction from Little Mac showing disgust from it, as well as a very humorous message from WVBA after the cut scene. He will also recover all of his stamina immediately after (this is inevitable). Also, if you don't hit the chocolate bar, he will recover stamina in the same manner as when you knock it out of Doc's hands the first time. Like King Hippo, you only need to knock him down once to KO him.