The St. Louis Cardinals seem poised to rock the winter trade market.

Likely turning to a multi-season rebuild around its younger players, the team could deal big-name veterans like Nolan Arenado and Sonny Gray. There will be a number of teams lining up with offers for the Cardinals’ best players and a trade proposed by Nate Hagerty of On SI has St. Louis linking up with the Boston Red Sox for a blockbuster deal.

“Trade proposal: the Red Sox would receive — right-handed pitchers Ryan Helsley and Eric Fedde,” per Hagerty. “The Cardinals would receive three top prospects from Boston — No. 3 utility man Kristian Campbell, No. 9 RHP Luis Perales and No. 21 RHP Hunter Dobbins.”

There’s no doubt that the headliner in this five-player pitch would be Helsley, who is coming off of his second-career All-Star season and 49 total saves, the most of any Major League Baseball pitcher. But it would also round out Boston’s rotation with a veteran hurler who won’t factor into the Cardinals’ long-term plan by adding Fedde.

“In what would be a stunning blockbuster, the Red Sox trade several top prospects to the Cardinals in exchange for Helsley — 2024 National League Reliever of the Year — and Fedde — a veteran starter with one season remaining on his extremely affordable contract,” Hagerty added. “This deal would help the Cardinals restock their farm system with three solid top prospects while clearing room in the rotation for pitching phenom Quinn Matthews. It might be a stretch but trading Helsley and Fedde to the Red Sox could yield high-quality investments for the franchise’s future.”

The Red Sox could be in the market for a shutdown arm like Helsley’s as their 2024 closer, Kenley Jansen, hits free agency. While this trade pitch has the Red Sox relinquish the number-10 prospect in all of baseball in Campbell, the team would hold onto Roman Anthony, Marcelo Mayer and Kyle Teel, preserving much of its top future talent.

As the Red Sox shift to a win-now focus and the Cardinals look further down the line, this proposal seems like it could fulfill needs for both teams. But as arguably the best reliever in baseball, Helsley is sure to have plenty of suitors and it would take a major haul to land him.