Seattle Mariners shortstop Colt Emerson. Mark J. Rebilas-Imagn Images

Mariners jump aboard the extension train by signing top prospect

By Zachary Cariola | Last updated Mar 31, 2026 11:10 AM ET

After the Milwaukee Brewers gave shortstop Cooper Pratt an extension — Pratt has never played a game in the major leagues — the Seattle Mariners decided to hop on the extension train. According to MLB Insider Robert Murray, the Mariners and infielder Colt Emerson are in agreement on an eight-year ($95 million) contract, which includes a ninth-year club option.

Emerson also has a full no-trade clause and escalators that can make the deal worth $130 million.

Emerson played at three levels in the Mariners organization last season (High-A to Triple-A) and batted .285 with a .842 OPS and 16 home runs in 130 games. In three games in Triple-A this season, he’s hitting .357 with a double, a home run and two RBI.

The Mariners are locking up their potential shortstop of the future

Emerson shouldn’t have long to wait to make his major league debut. The Mariners drafted Emerson in the first round (22nd overall) in the 2023 MLB June Amateur Draft from John Glenn High School in New Concord, OH.

Mariners' everyday shortstop J.P. Crawford is on the injured list (shoulder) and has not played a game this season. In seven games in the spring, Crawford batted .125 with a .292 OPS.

Entering the final year of his five-year, $51 million contract, the Mariners are likely to let Crawford walk and hand Emerson the reins. With a looming work stoppage potentially stopping the 2027 season, the Mariners and others are making sure to lock up their prospects before the doors for making deals close. At 20 years old, Emerson would get the chance to become a free agent at 29, still in the prime of his career.

The Mariners' giving Colt Emerson an extension shows their willingness to spend internally

The practice of giving long-term deals to prospects before hitting the major leagues is nothing new. The Detroit Tigers signed infielder Colt Keith to a six-year, $28.642 million contract in January 2024 and the Boston Red Sox signed infielder Kristian Campbell to an eight-year, $60 million contract in April last year.

The Mariners aren’t known for spending money in free agency, with first baseman/designated hitter Josh Naylor (five years, $92.5 million) being one of the bigger names signed by them since Robinson Cano (10 years, $240 million). Rated as the Mariners' best prospect, locking up Emerson does show the Mariners will spend money.

Ace right-hander Logan Gilbert and right-hander George Kirby are also eligible for extensions. The Mariners had the seventh-best starting rotation in the American League in 2025 (3.97 ERA). Locking up two pieces of the rotation that got the Mariners one game short of the World Series should be next on Jerry Dipoto’s the to do list.

Zachary Cariola

My name is Zachary Cariola and I have been a sports fan for as long as I can remember. My areas of expertise are MLB, NBA, and NFL. When I’m not writing, I love spending time with my family and learning history.

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