Former Diamondbacks All-Star Signs Deal with Blue Jays

According to the MiLB transaction log, former Arizona Diamondbacks All-Star left-hander Joe Mantiply has signed a deal with the Toronto Blue Jays.

It's a minor league deal for the veteran southpaw — his first opportunity since being released by Arizona.

Former Arizona Diamondbacks All-Star Joe Mantiply Signs with Blue Jays

Mantiply, 34, struggled throughout the 2025 season after serving as one of the most reliable and effective relievers in Arizona's bullpen from 2021-2024.

He threw to an excellent 2.85 ERA in 2022, earning the D-backs' lone All-Star berth that season.

But Mantiply's effectiveness took a major dive to open 2025. In 9.2 innings, he was knocked around for 17 earned runs, including three homers.

For a pitcher that never relied on the velocity of his stuff, it was exceptionally devastating when his command wavered. His sinker, which was not much of a velo offering to begin with, began to dip down to around 88 MPH.

Mantiply began to leave too many slow pitches in hittable spots, and was blown up for multiple runs in five of his 10 major league appearances this season.

A particularly devastating outing against the Chicago Cubs at Wrigley Field led to a quick trip down to Triple-A Reno.

Unfortunately, Mantiply did not fare much better in the offense-heavy Pacific Coast League.

He sported a 5.56 ERA, including a five-run blowup outing in 10 Triple-A appearances. Mantiply was recalled on May 10, optioned back five days later, then eventually designated for assignment on May 30.

Two days later the former All-Star was released by the Diamondbacks — ending a six-year tenure in the desert with a 4.32 ERA, but a 3.29 Fielding Independent Pitching.

That peripheral disparity has been a calling card for the southpaw, even in his more effective years.

Manager Torey Lovullo trusted him to take on some of the toughest hitters in baseball, and poor outcomes often did not match how well Mantiply was executing.

Mantiply went unsigned for over a month, but will now join Toronto's rookie ball club for the time being.

The Blue Jays' 3.57 bullpen ERA ranks eighth in baseball. They likely are not in dire need of support at the major league level.

Meanwhile, the Diamondbacks' bullpen continues to struggle amongst a growing list of injuries. With Jalen Beeks going on the Injured List, Kyle Backhus is now the only viable left-hander in Arizona's group of relievers.

The D-backs are 27th in bullpen ERA at 4.94, which, if you can believe it, is not an insignificant improvement over recent series.

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