Complex sentence: Former teammate Jimmy Wynn mentioned in his autobiography that Walt Bond; an African-American former Astros player, who died from leukemia while still active jersey number wasn't retired by the club after his death despite playing more games than Umbricht.
Split into simpler sentences: Former teammate Jimmy Wynn mentioned in his autobiography that Walt Bond, an former Astros player who was African-American, died from leukemia while he was still active. His jersey number was not retired by the club after his death despite appearing in more games in a Astros uniform than Umbricht.