Who says no in a potential deal where the Cardinals would acquire Bryce Miller or Emerson Hancock for a package including Ivan Herrera and Riley O'Brien going to the Mariners? That is just one iteration of a deal that could potentially fill dire needs for both clubs.
The Cardinals (54-55) and Mariners (53-57) need late-season jolts with both clubs going 3-7 over their previous 10 games to leave themselves scrambling to get a Wild Card slot. A St. Louis squad that has lost 10 of 14 since the All-Star break will need to leapfrog five teams in the standings after falling three games out of the final Wild Card slot in the National League. Meanwhile, a Mariners team that came within one win of reaching the World Series in 2025 will similarly need to scramble to get into the postseason after dropping to 11th in the American League.
Seattle’s offense has been a disappointment all season with AL MVP Cal Raleigh struggling and Donovan being unable to stay on the field because of a groin/hernia injury originally suffered last July while playing for the Cardinals. Hitting left-handed pitching has been a huge problem for the Mariners as they rank 29th in MLB in batting average (.220), 28th in on-base percentage (.301), 28th in slugging (.345) and 29th in OPS (.646) versus southpaws.
Meanwhile, a Mariners squad deep in starting pitching depth has also had struggles hanging onto late leads and closing out games. Even though Andres Munoz has been a revelation with 19 saves in 24 opportunities, Seattle could still use more high-leverage arms in its bullpen.
Could a Cardinals club in desperate need of a frontline starting pitcher pry one away from the Mariners by offering All-Stars Ivan Herrera and Riley O’Brien? Or, if the Cardinals are reticent to surrender that much, could they offer lefty reliever JoJo Romero to the Mariners instead of O’Brien for a starting pitcher?
While the Mariners would likely resist dealing Logan Gilbert (8-6, 3.44 ERA) or Bryan Woo (7-8, 4.56 ERA), they might be willing to part ways with 27-year-old Bryce Miller, 28-year-old George Kirby or 27-year-old Emerson Hancock.
Hancock, the No. 6 overall pick of the 2020 MLB Draft, is 6-5 with a 3.26 ERA over 20 starts this season. He has 102 strikeouts in 110 1/3 innings and he has surrendered 14 home runs. Kirby, another right-hander, is 8-9 with a 3.98 ERA in 20 starts, but foes have battered him for a .280 batting average and 15 homers.
Miller, who missed 2 ½ months with an oblique strain, has a 2.75 ERA over 12 games (11 starts) and foes have hit just .207 against him. Miller had a breakout season in 2024 when he went 12-8 with a 2.94 ERA and 171 strikeouts in 180 1/3 innings, but he’s regressed over the past two seasons because of injuries and consistency issues.
Would Cards deal Herrera, O'Brien or Romero?
Herrera, 26, has started to show signs of coming out of a six-week funk offensively by racking up nine hits over his last six games. He capped a three-hit game on Wednesday with a two-run, game-winning double for the second walk-off hit of his career.
Herrera, the longest-tenured Cardinals player on the roster, is hitting .246 with 12 homers and 46 RBI. He has an .823 OPS against left-handers this season with five of his homers coming against southpaws.
However, Herrera likely doesn’t fit into the Cardinals long-term plans as a catcher because of his struggles in throwing out base stealers. He has surrendered 21 stolen bases this season without a caught-stealing throw, and he hasn’t thrown out a base stealer since September of 2024 when superstar Juan Soto – then a member of the Yankees – was mowed down while trying to swipe second.
O’Brien, a native of Seattle, pitched for the Mariners in 2022 before being designated for assignment and later traded to the Cardinals. He showed tremendous flashes of success in 2025 when he went 3-1 with a 2.06 ERA, six holds and six saves in nine chances as an evolving high-leverage reliever. His breakout season came this year when he assumed full control of the closer’s role, and he has saved 26 games in 31 opportunities. The 26 saves are good for the second-most in the NL.
Romero, 28, is set to become a free agent at season’s end. While crafting a fourth straight strong season for the Cardinals, Romero was hit with an appendicitis during the MLB All-Star break and he hasn’t pitched since July 12. Still, he’s posted a 3.35 ERA in 43 innings in 2026 while primarily working as a set-up reliever in front of O’Brien.
