Daisuke Komori is a childhood friend of Goro. Komori was Honda's catcher since his earlier days as a little leaguer back when they were in Mifune Dolphins along with Sawamura and Shimizu.
At the beginning of season 1, he was being bullied by Sawamura but was helped by Gorō, as he invited him to join Mifune Dolphins, and solved the problem.
In season 2, He continued to catch for Gorō when he returned from Fukuoka at Mifune East Middle School, but his middle school baseball days ended when Mayumura of Kaido Affiliate Middle School eliminated them single-handedly in the first round of middle school nationals.
In season 3, Gorō left Kaido and was planning to enter Mifune High. However, as he saw Komori (as the catcher), Yamane (as the ace pitcher) and Oobayashi (as third hitter) already have their own fully functioning team, he went on and made a new team at Seishuu High. They were rivals. Komori really wanted to win, and planned very carefully to beat Gorō's team. However, Gorō eventually won the match, after Komori and the others put on a good fight. After the match, Gorō saw Komori at a footbridge and asked him to play catch. Komori came to accept the end of his high school baseball days.
After high school, Komori went on to play for his university as their pinch hitter. He is later seen coaching Mifune Dolphins during OVA 1, "Message".