Two Rental Aces That Could Shake Up the Deadline

We are just a week into June, but July plans are beginning to bloom as the madness of the Trade Deadline looms. The picture is far from clear across many divisions, but one thing is coming into sharp focus: it’s a seller’s market, especially for starting pitching. And Framber Valdez and Zac Gallen stand out as potential aces on the move.

Both are impending free agents. Both have playoff experience. Both have ace-level talent, even if one is struggling more than expected in 2025. And both could tilt the postseason race depending on where they land.

Why the D-backs Could Shop Gallen

On Episode 891 of the Just Baseball Show, JustBaseball.com Managing Editor Ryan Finkelstein noted something that’s becoming increasingly obvious: with Corbin Burnes sidelined, the team’s recent slide, and the overall state of their pitching staff, the Arizona Diamondbacks may pivot to sell mode.

They sit fourth in a loaded NL West, trailing the Dodgers, Padres and Giants, and they’ve fallen to 10th in the NL standings, 5.5 games out of a Wild Card spot.

Despite their top-3 team slugging percentage, the pitching staff sits with a 4.76 ERA (24th in MLB), and with both Zac Gallen and Merrill Kelly set to hit free agency, Arizona could cash in on their arms instead of risking them walking for nothing.

Gallen, 29, isn’t pitching like himself this season. Through 13 starts, he’s 4-7 with a 5.13 ERA, 1.33 WHIP, 70 strikeouts and 33 walks across 73.2 innings. He’s already surrendered 11 home runs and has posted just 0.3 WAR on the season. But the broader resume still shines.

From 2022–2024, Gallen was a workhorse: 542 innings, an ERA just over 3.00, and 12.3 WAR, with two top-5 finishes in NL Cy Young voting and a 2023 All-Star nod. He even helped Arizona reach the 2023 World Series, tossing 33 playoff innings with a 4.54 ERA.

The advanced metrics suggest he can still return to his regular form. His expected ERA is 3.88, suggesting some positive regression. And despite clear concerns, like his declining fastball and breaking ball effectiveness, lower chase and strikeout rates and a higher walk rate, his xBA and xSLG are in line with recent years.

A new team and coaching staff could refine his usage: less reliance on the four-seamer (46.3% usage), increased use of his cutter (7%), a refined knuckle curve (23.7%), and more frequent changeups (13.9%).

Gallen’s 3.45 road ERA this year (compared to 6.38 at home) adds to the case for a scenery change.

The Case for Framber Valdez as a Deadline Headliner

Then there’s Framber Valdez, the Astros’ southpaw ace. Houston currently leads the AL West, but with the Mariners looming and the Rangers capable of a surge, nothing is guaranteed.

If Houston stumbles in July or decides not to risk losing Valdez for nothing, the 31-year-old could become the most coveted starter on the market.

Valdez is putting together a typically great season: 3.07 ERA, 1.06 WHIP, 84 Ks and 2.2 WAR across 13 starts and 85 innings. He’s already racked up 10 quality starts and even tossed an 83-pitch complete game against Tampa Bay. His 96th percentile ground ball rate is elite, thanks to a sinker he throws nearly half the time. That pitch has generated +9 run value, placing him in the 94th percentile for fastball effectiveness per Baseball Savant.

There are a few blips, as he can get hit hard at times, and his walk rate is only average, but the strikeout rate and chase rate remain strong, and few pitchers have been as consistently valuable over the last five seasons.

Since 2020, Valdez has posted a 16.9 WAR, thrown 175+ innings in three straight seasons, and earned All-Star nods in 2022 and 2023. His playoff pedigree is legit too: 85 career postseason innings with a 4.34 ERA, highlighted by a 1.44 ERA across four starts during the Astros’ 2022 title run.

Who Might Trade for Them?

Let’s start with Zac Gallen. A trade to a division rival like the Dodgers or Giants is almost certainly off the table. But an NL Central or East club? That’s very possible.

The Mets are intriguing. Their rotation, consisting of Kodai Senga, Tylor Megill, David Peterson, Clay Holmes and Griffin Canning, is outperforming expectations, but lacks reliable top-end dominance. Gallen, a New Jersey native who played college ball at UNC, could be a compelling fit in Queens.

The Yankees are also likely to make a move considering Gerrit Cole is out for the year. Max Fried leads the staff, Carlos Rodón has been a great No. 2 and Ryan Yarbrough has stepped up big, but adding Gallen would deepen their October rotation. The Blue Jays, Twins and Guardians are all wild cards in the mix depending on their July trajectory.

Three NL Central teams to watch:

• The Cubs, with a top-tier offense and Justin Steele done for the year, could use an arm like Valdez or Gallen. They have a deep farm system and could go big.
  
• The Cardinals, who originally drafted Gallen, could bring him home to fortify a rotation already anchored by Sonny Gray, Erick Fedde and supported by a breakout from southpaw Matthew Liberatore.
  
• The Brewers, like the Mets, have a rotation overachieving, but they are also a starter short and have logged the second-most bullpen innings in the league. A reliable innings-eater like Valdez or Gallen could help stabilize things, though Milwaukee’s prospect capital is more limited.
  

As for Valdez, if Houston does sell, the Dodgers and Padres could be front-runners. Both are in contention and could use a durable left-handed starter. The Padres could use someone to complement Michael King and help offset Dylan Cease’s inconsistency.

The Dodgers’ pitching injuries have been well-documented, and question marks in the current rotation behind Yoshinobu Yamamoto could inspire a front office motivated to repeat as champions.

A Padres-Dodgers bidding war for Valdez would be electric, and it wouldn’t be the first time those clubs clashed at the deadline.

These Rental Aces Scream October-ready. 

Gallen brings strikeout potential, postseason experience and a fiery presence that could thrive with the right adjustments. Valdez is as dependable as they come, a ground ball wizard with deep playoff experience and a sinker that neutralizes power hitters.

If either, or both, are moved, it could dramatically shift the balance of power down the stretch. All it takes is one contender to get aggressive.