Thornton (0-1) took the loss against the Diamondbacks on Sunday, allowing an earned run on a hit and a walk over one inning.

Thornton has pitched 4.2 innings across five Cactus League appearances, allowing four runs (two earned) on three hits and four walks while recording two strikeouts.

Thornton signed a one-year, $1.2 million contract with the Mariners on Thursday to avoid arbitration, Daniel Kramer of MLB.com reports.

Thornton (0-2) took the extra-innings loss against the Angels on Monday, allowing three unearned runs on two hits over one-third of an inning. He struck out one.

Thornton will serve as the Mariners' opening pitcher Saturday against the Rays, Daniel Kramer of MLB.com reports.

Thornton (0-1) took the extra-inning loss against the Orioles on Sunday, allowing two runs (one earned) on two hits over one inning. He struck out one.

The Mariners recalled Thornton from Triple-A Tacoma on Tuesday

The Mariners acquired Thornton from the Blue Jays on Wednesday in exchange for Mason McCoy, Jeff Passan of ESPN.com reports.

Thornton was designated for assignment Friday, Arden Zwelling of Sportsnet.ca reports.

The Blue Jays optioned Thornton to Triple-A Buffalo on Saturday, Keegan Matheson of MLB.com reports.