SEATTLE — Since the day Julio Rodriguez signed as a 16-year-old out of the Dominican Republic, the Seattle Mariners have known they have something special.

And as he grew from potential-filled prospect to baseball phenom to everyday center fielder and now the face of their franchise, the idea of him wearing any other uniform but theirs six years from now wasn’t an option.

Now they are making sure he remains a Mariner for years to come by giving him a massive, long-term contract extension.

Major League Baseball sources confirmed an initial report by MLB.com’s Jesse Sanchez that the Mariners and Rodriguez are close to finalizing an extension with more than $200 million in guaranteed money that could reach $450 million with bonuses and incentives.

ESPN’s Jeff Passan reported that the deal is for 14 years and includes player and team options. The structure of the deal is one of the most unique in baseball history.

According to Passan, the base frame of the contract is eight years and $120 million, including this season. But after the 2028 season, the Mariners must make a decision on a club option, which is based on Rodriguez’s performance in MVP voting, determining the length and salary of the option.

That option is for either eight or 10 years added to the original deal with a range anywhere from $200 million to $350 million.

If the Mariners decline the club option after Year 7, Rodriguez then is granted a player option after Year 8 for five years and $90 million. That’s why he is technically guaranteed $210 million. If Rodriguez were to decline the option, he would be a free agent at age 29.

As a 21-year-old rookie, Rodriguez has been the Mariners’ best player. In 108 games, he has a .269/.328/.471 slash line with 19 doubles, three triples, 20 homers, 64 RBI, 64 runs scored and 23 stolen bases. Per Baseball Reference, he has 4.3 wins above replacement, which is highest on the team.

With a solo home run Wednesday, he became the first Mariners player to tally 20 homers and 20 stolen bases in a season since Mike Cameron did it in 2003, and the first rookie to do it since Marty Cordova of the Twins in 1995. He reached 20 homers and 20 stolen bases faster than any player in American League history, accomplishing it in 107 games. That surpassed Mike Trout, who did it in 112 games.

RAYS: Tampa Bay right-hander Tyler Glasnow signed a $30.35 million, two-year contract that will delay the start of his free agency by one year, the team announced.

The Rays’ Opening Day starter last year hasn’t pitched this season after undergoing Tommy John surgery on Aug. 4, 2021. He went 5-2 with a 2.66 ERA in 14 starts last year.

Glasnow is making $5.1 million this year. He will get $5.35 million next season and $25 million in 2024, which is the first year he would have been eligible for free agency.

Glasnow has thrown batting practice twice since Aug. 20, and topped out at 97 mph during a session on Tuesday. The 29-year-old has not ruled returning before the season ends.

PHILLIES: Bryce Harper was back in Philadelphia’s starting lineup for Friday night’s game against the Pittsburgh Pirates after missing 52 games because of a broken left thumb.

Harper is batting .318 with 15 homers and 48 RBI in 64 games. He went 5 for 8 with two homers, two doubles and six RBI in a pair of rehab games at Triple-A Lehigh Valley on Tuesday and Wednesday.

RANGERS: Former AL Cy Young Award winner Dallas Keuchel was added to the Texas taxi squad on Friday and is scheduled to start Saturday at home against the Detroit Tigers.

Keuchel, 34, was signed to a minor league contract on July 25, five days after the Arizona Diamondbacks designated him for assignment. He went 0-2 in four starts for Arizona after beginning the year 2-5 in eight starts for the Chicago White Sox.