Drey Jameson Could Be Solution to Diamondbacks' Bullpen Dilemma

Drey Jameson has been a darling pitching prospect in the Diamondbacks' organization since he was selected 34th overall in the 2019 Draft. He has found success in the majors in a mix between starting and relief, pitching to a career 2.63 ERA, but an injury held him out for the entire 2024 season.

Now, he is back and already carving up hitters with his dominant pitch mix. With veteran reliever Joe Mantiply facing major struggles to begin the young season, this could be the time for Drey Jameson and his triple-digit fastball to join Arizona's relief corp once and for all.

In order to continue to rehab and ramp up for the season the 27-year-old flamethrower started the year with the Reno Aces. This was a shock to some, since he dominated to the tune of a 1.59 ERA across six appearances in Spring Training.

Manager Torey Lovullo and general manager Mike Hazen have made it clear that had he been ramped up enough, that he may well have made the MLB roster out of camp. Still, Jameson has been ticking the right boxes, and has continued to showcase how dominant he can be.

With the Aces he has pitched in 6.2 innings to start the year. Over that span he has a 2.70 ERA and has surrendered eight hits. Those numbers should take a dip down as he has faced some poor luck in the home run department, surrendering two longballs for his only runs of the season.

This comes on a small sample size 66.7% HR/FB ratio, something which is quite unsustainable, and which is undoubtedly aided by the Aces' offense-friendly environment.

Despite the home runs he has looked quite sharp. He has walked none and struck out ten batters, setting his K/9 at 13.5. The right-hander throws five pitches, each of which work well off one another and generate a great deal of whiffs.

The headliners are of course his fastball and sinker, each of which are thrown in the high 90 mile per hour range, often hitting the triple digit marker. Another star in his arsenal is his slider which in 2023 he threw 26% of the time, and works as a strong putaway pitch.

While it may have been inevitable to see Drey Jameson at a major league level in 2025, it now seems that will be sooner rather than later. The Diamondbacks' bullpen as a whole has been very effective to start the year, with unexpected breakout stars Jalen Beeks and Shelby Miller working in tandem with Ryan Thompson, A.J. Puk and Justin Martinez at the back end.

However, there has been a stark outlier from the group. This is former All-Star and lefty specialist Joe Mantiply, who has a 15.95 ERA in 7.1 innings pitched.

It became especially evident on Friday, during a blown game to the Cubs when Mantiply allowed three runs on four hits in just 2/3 of an inning, that the team cannot keep putting him on the field. His sinker velocity is down to around the 88 MPH range, and he can no longer effectively locate, leading to a hard contact rate that cannot be ignored.

As the whole D-backs' relief group is currently worn out, a move for a fresh arm for Jameson would make sense, as they are now on the back foot against the Cubs. They sit only one loss away from dropping the season series to Chicago, something which could cost them dearly later in the season.

Mantiply still has two options remaining, leaving the Diamondbacks a difficult but obvious choice to make. With Jameson continuing to perform at his level, it isn't a matter of if, but when Mantiply is sent down. Even though Jameson may not be left-handed, the Diamondbacks are likely a better club right now with him on the team over Mantiply.

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