|User(s)|| Itagaki Manabu|
When Itagaki Manabu enters a state of full concentration, he can move so fast that his opponents seem extremely slow. Seeing this ability,Mashiba Ryou commented that Itagaki is in equal (in terms of speed) or he might even be faster than Miyata Ichirou. In his battle with Karasawa, he rose up to his 2nd gear after focusing on little to big objectives making himself seem like he's teleporting when was swaying back and forth really fast.
In his prior match before fighting Hoshi in Osaka, Bullet Time appeared twice during the match but it caused Itagaki trouble as his boxing sense became distorted which caused him to take hits. Ippo commented that he was reacting too fast during the fight which messed up the timing of his attacks. His trainer,Shinoda Tomoyuki was so sure of Itagaki's genius potential that he vowed to resign if he lost the match against Hoshi. This ability helped him dominate the match as Hoshi was unable to touch Itagaki during the whole bout. Itagaki launched a devastating counter to Hoshi's jaw which gave him a down and later knocked him out with 5 quick hits to the jaw. This seemed to be a good way to stop in-fighters who would normally go for a dual exchange when facing faster opponents in the ring.
The idea of Bullet Time is that the user's body and reflexes are so fast that their eyes and senses register every movement as if it is happening in slow motion. This leaves the opponents vulnerable to precise counters which can be thrown before they realize they've been hit. This raises the effectiveness of the user's blows as they could land out of an opponent's blind spot, causing both high mental and physical damage. The user moves faster than the opponent can visually track which makes it seem like the person "vanishes" within the ring itself. Takamura said it's like looking out from inside a high speed vehicle, everything else is in super slow motion.
Bullet time is dependent on Itagaki's stamina but most importantly his concentration. Despite its speed, this skill can be disrupted by static given off from switching styles making it weak to switch hitters like Randy Boy Junior who knocked Itagaki down during a spar. Fast boxers like Saeki Takuma can exist in this "time" as they have the needed physical abilities to manifest it albeit differently as Itagaki's space was invaded by Saeki, nulling the slow motion effect.
Takamura on the Hoshi match: "They're both in the same ring and same space, but they're running on different times."