Kurogane, Haikyuu!! Recommendations
Kurogane and Haikyuu!! are competitive series with a colorful cast of characters. The main male protagonist are involved in an activity/sport that tests the limits of their physical abilities. While they start out as underdogs, the series shows their hard work and determination as they begin to demonstrate superior skills. Both series focuses a lot of characterization and relationship dynamics as well. Kurogane is also noticeable for its supernatural element while Haikyuu!! retains a strong degree of its realism with its game mechanics.
Both revolve around team sports that are focused very much on competitions and both do a good job in building up the atmosphere and tension in these events. They also have strong and developed rivals and can be understood by someone with no prior knowledge of the sport as they explain the rules and techniques of each sport rather well. The protagonists start off relatively weak and inexperienced but have hidden talent within them and struggle to catch up with the better and more experienced members of their team.
Both are shounen team sports manga, with a very colorful cast of characters, many competitions, and a very strong rival for the Mc that he strives to overcome.