Mariners Promote MLB’s No. 6 Prospect to Help in AL West Race

The Seattle Mariners are calling up one of the top overall prospects in the game.

Feb 23, 2026; Phoenix, Arizona, USA; Seattle Mariners shortstop Colt Emerson against the Los Angeles Dodgers during a spring training game at Camelback Ranch-Glendale. Mandatory Credit: Mark J. Rebilas-Imagn Images | Mark J. Rebilas-Imagn Images

The Seattle Mariners are calling up the No. 6 overall prospect in baseball.

Right now, the Mariners are in third place in the American League West at 22-25. The offense hasn't been fully clicking and the Mariners lost All-Star Brendan Donovan to the Injured List on Sunday due to a left groin muscle strain. In response, Mariners top prospect and MLB's No. 6 overall prospect Colt Emerson has been promoted to the big leagues to take over as the club's primary third baseman, per Daniel Kramer of MLB.com.

"Colt Emerson will be the Mariners' primary third baseman moving forward, per Justin Hollander," Kramer wrote. "Brendan Donovan will receive a PRP injection in the groin strain, as well as a different injection in his adductor. They're hopeful he can get back to baseball activity in 2-3 weeks."

AL West Impact Of Colt Emerson's Promotion

Feb 24, 2026; Peoria, Arizona, USA; Seattle Mariners shortstop Colt Emerson (85) after a hit against the Chicago White Sox during the fifth inning in Peoria, Arizona. Mandatory Credit: Arianna Grainey-Imagn Images | Arianna Grainey-Imagn Images

Emerson has star potential. He's just 20 years old and was a first-round pick by the Mariners back in 2023. He has quickly worked his way through the Mariners' farm system. The 2025 season is the perfect example of what he can be. He played in 130 games across High-A, Double-A and Triple-A. He filled up the box score on a nightly basis and finished the season slashing .285/.383/.458 with an .842 OPS, 16 homers, 78 RBIs, 14 stolen bases, 71 walks, 28 doubles, six triples and 82 runs scored.

So far this season, he is slashing .255/.347/.469 with an .816 OPS, seven homers, 26 RBIs, 10 stolen bases, eight doubles and 26 runs scored in 38 games played. The Mariners are 22-25 on the season so far and are in third place in the AL West behind the Athletics and Texas Rangers. It's tough to lose a guy like Donovan for any amount of time, but Emerson has the upside to replace him for the time being.

The Mariners' starting rotation has been excellent so far this season, unsurprisingly. The offense hasn't been as good. Donovan has been very good. It's tough to lose him, but the beauty of Donovan is the fact that he can play all over the place. If Emerson can come in and play well, then the Mariners can move Donovan elsewhere around the diamond to help elsewhere. It's tough to lose Donovan, but the Mariners fortunately have one of baseball's most intriguing prospects to turn to right now.

The Mariners should be able to continue to fight for a top spot in the AL West, even without Donovan.