According to the official website, the Blu-ray volume 1 of Taishou Yakyuu Musume.
includes an extra short anime "Kon-ya no Watashi wa Romantic Strike".
The members of Ohka-kai heard of a rumor of an equipment called "Kondara", which is essential to baseball. As they discuss what a Kondara is, the hot debate goes into a confusion by the excited members. Finally Koume decides to look for Kondara, but Anna is also excited and cannot be counted on.
Kondara is a Japanese slang of a roller used to level the ground.
Source: Taisho Yakyuu Musume. official website