Seattle Mariners, Julio Rodriguez finalizing long-term extension that could max out at $470 million, sources confirm

Star rookie Julio Rodriguez and the Seattle Mariners are finalizing a massive long-term extension that guarantees the 21-year-old outfielder $210 million and could max out at $470 million, which would be the richest deal in American sports history, sources told ESPN on Friday.

The deal, which is expected to be announced soon, offers a number of iterations, sources said. The base deal is for $120 million and lasts through the 2029 season. Following the 2028 season, the Mariners can exercise an option for an additional eight or 10 years, depending on where Rodriguez finishes in MVP voting in the preceding seasons.

If the Mariners turn down the option, Rodriguez can exercise a five-year, $90…