Seattle Mariners Executive Vice President and General Manager of Baseball Operations Justin Hollander announced that the club has claimed catcher off waivers from the Toronto Blue Jays.
With the move, Seattle’s 40-man roster now stands at 38 players.
MacIver, 29, will join Triple-A Tacoma. He has played 74 Triple-A games between the Blue Jays and Texas Rangers organizations this season, hitting .253 (68-for-269) with 37 runs, 16 doubles, three triples, eight home runs, 50 RBIs and five stolen bases. He has posted a .342 on-base percentage, a .424 slugging percentage and a .766 OPS.
The catcher has also appeared in 32 MLB games, all coming with the Athletics in 2025. During that stretch, he batted .186 (19-for-102) with five doubles, three home runs, nine RBIs and a .576 OPS.
MacIver, who is from Pleasant Hill, California, was originally drafted by the Colorado Rockies in the ninth round of the 2018 MLB First-Year Player Draft after playing at the University of Washington.
Since being selected, he has spent time in the Rockies’ organization from 2018 through 2024, followed by stints with the Athletics in 2025 and the Rangers and Blue Jays in 2026. Across 657 minor league games, MacIver has compiled a .263 batting average (617-for-2,345), along with 347 runs, 131 doubles, 20 triples, 81 home runs, 379 RBIs and 84 stolen bases. He has also produced a .350 on-base percentage, a .440 slugging percentage and a .789 OPS.
Should MacIver make his MLB debut with Seattle, he would become the seventh University of Washington product to appear in a game for the Mariners. He would join Austin Voth (2024), Jake Lamb (2022), Braden Bishop (2019-21), Sean White (2007, 2009-10), Sean Spencer (1999) and Mike Blowers, who played for Seattle from 1992-95, 1997 and 1999.
