The St. Louis Cardinals are full-blown sellers ahead of the 2023 MLB trade deadline. There's no turning back with only a few hours left until the clock strikes 6 p.m. ET. Every Cardinals player who is headed for free agency should be shipped off to a contender. With Jordan Montgomery, Jordan Hicks and Chris Stratton already leaving for greener pastures, one last-minute Cardinals' trade should be executed before the 2023 deadline arrives.

St. Louis technically isn't having the fire sale that some observers believe is necessary. Paul Goldschmidt and Nolan Arenado are expected to stay put. The Cardinals plan to have the reigning NL MVP and the superstar third baseman part of a core that contends for the NL Central title in 2024. Both players are under contract next year. Arenado is signed through the 2027 campaign.

The Cardinals have admitted defeat for the 2023 season. Rightfully so. Stuck in last place and trailing the first-place Cincinnati Reds by 11.5 games, St. Louis is going nowhere over the final two months.

Who must the Cardinals trade before the 2023 deadline?

Cardinals must trade SP Jack Flaherty

It makes no sense for the Cardinals to keep Jack Flaherty beyond the 2023 trade deadline. Flaherty is in the last year of his contract and set to become a free agent. The 27-year-old is 7-6 with a 4.43 ERA and a 1.55 WHIP on the day of the trade deadline. Flaherty has posted a 4.25 ERA or higher in three of the last four years, a span that has been highlighted by injuries. Flaherty's production and injury history make him a player that St. Louis should probably move on from in the offseason anyway.

Despite a disappointing handful of seasons, Flaherty probably still has some value on the trade market. Justin Verlander is the top pitcher on the market. There's a considerable drop-off after the New York Mets' starter. A contender who doesn't want to pay Verlander's asking price might turn to the Cardinals for Flaherty, who is a cheaper option but has potential upside as a playoff starter.

Flaherty was an ace before the pandemic. He's made four career playoff starts, three of which were quality starts. Flaherty pitched to a 3.03 ERA in five July starts, and he's healthier than he's been since 2019.

Once the Cardinals decided to trade Mongomery, it should've sealed Flaherty's fate.

Possible Jack Flaherty trade deadline suitors 

All of the teams that miss out on the Justin Verlander Sweepstakes are logical destinations for Flaherty. The Houston Astros are reportedly in the driver's seat for the three-time Cy Young winner. Verlander has a no-trade clause, so he could potentially direct his way to Houston if the Mets are intent on shipping out the veteran.

The Boston Red Sox, Baltimore Orioles, Cincinnati Reds, Los Angeles Dodgers, Arizona Diamondbacks and Atlanta Braves are all in the market for starting pitching, according to The Athletic's Ken Rosenthal. The Detroit Tigers have reportedly set the asking price high for Eduardo Rodríguez and Michael Lorenzen. Maybe a fringe playoff team, like the Red Sox, will settle for a marginal upgrade in Flaherty. The Red Sox could certainly benefit from a trade with the Cardinals, given that their starters have a combined 4.72 ERA.

Any kind of upgrade would help the Reds. Cincinnati has managed to take hold of first place in the division with an abhorrent 5.21 from its starters. The Diamondbacks are in a similar position, desperate for any help with a 6.10 ERA in the last 15 days.