Right-hander Hunter Greene and the Cincinnati Reds are in agreement on a six-year, $53 million contract extension, the team announced Tuesday, tying the hardest-throwing starter in baseball long-term to the organization that previously didn't have any salary guaranteed to players beyond this season.

Greene, 23, debuted last year as Cincinnati's rebuild remained a work in progress. The arrival of starters Nick Lodolo and Graham Ashcraft alongside Greene have brought some semblance of hope back to an organization that, outside of the COVID-shortened season, last made the playoffs in 2013.

The deal starts this season and buys out two years of Greene's free agency, with a $21 million seventh-year club option that includes a $2 million buyout. If the Reds pick up the option, Greene would hit the open market after his age-29 season. The deal, which is the largest the Reds have given to a player before he reaches arbitration, can max out at more than $90M with escalators.

Signing pitchers at this age is a rarity -- Greene joins Felix Hernández and Atlanta Braves star Spencer Strider as the youngest extended -- but Greene brings a rare blend of qualities. His fastball sits around 99 mph and has topped out at 102 this season. But his slider, which he now throws around 40% of the time, may be his most effective pitch.

Even if he doesn't develop a third pitch to regularly use, Greene can more than subsist on the offerings he's got. After striking out 164 over 125 2/3 innings during a rookie season in which he posted a 4.44 ERA, Greene has struck out batters at an even higher rate in his four starts this season. While his ERA is 4.24, Greene has been saddled with a .413 average on balls in play. Once that normalizes, his ERA likely will follow.

Chosen with the No. 2 pick in the 2017 draft out of the Los Angeles area, the 6-foot-5, 240-pound Greene underwent Tommy John surgery a little more than a year later and missed the 2019 season. He spent 2020 at the Reds' alternate site and went more than 2½ years between competitive games before spending 2021 and Double-A and Triple-A.

The Reds placed Greene on their Opening Day roster last year, and he started the first game this season for a team that is 7-9 after going 3-22 to begin 2022. Cincinnati, already carrying one of the lowest payrolls in the major leagues, previously had only $6.25 million committed in future years: $4 million to cover the option buyout of released infielder Mike Moustakas, and $2.25 million for buyouts on first baseman Wil Myers and catcher Curt Casali's mutual options for 2024.

More than half of Cincinnati's estimated current payroll of $83 million is going to longtime star Joey Votto, who is on the injured list, and Moustakas.

The Reds farm system is regarded as one of the best in the game, with the dynamic Elly De La Cruz on the cusp of the majors and the two gems of Cincinnati's trade of Luis Castillo last July, shortstop Edwin Arroyo and third baseman Noelvi Marte, not far behind.