Which team was the first professional baseball team, in 1869?

Which player struck out Mike Trout to end the 2023 World Baseball Classic final? Which two teams played the first MLB games in London in 2019? Which two teams opened the 2025 MLB season with games in Tokyo? Which city is traditionally honored with MLB's first Opening Day game due to its first pro team history? With which team did Derek Jeter spend his entire career? With which team did Tony Gwynn spend his entire career? With which team did Cal Ripken Jr. spend his entire career? With which team did George Brett spend his entire career?