From The Athletic's baseball-centric newsletter The Windup (no link, it's subscriber-only):
[A]ccording to sources briefed on the matter, the Red Sox had extensive discussions about trading Turner to the Marlins, a team that pursued him last offseason.
The Marlins felt they were close to acquiring Turner. When the proposed deal fell through, they pivoted to trades for two other hitters, Josh Bell and Jake Burger. What the Red Sox would have received in return for Turner is not known. But for president of baseball operations Chaim Bloom to again consider disrupting his clubhouse in the middle of an encouraging season, the package must have been enticing. The Marlins are deep in controllable starting pitching, precisely what Bloom was seeking to acquire at the deadline.
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The Red Sox were among the teams that got shut out in the thin starting-pitching market, along with the Dodgers, Diamondbacks, Braves and Reds. But according to sources, they were one of the clubs that pursued a deal for the most accomplished starter who did get moved — three-time Cy Young Award winner Justin Verlander.
The Mets ultimately sent Verlander to his preferred choice, his previous team, the Astros. Verlander, who is under contract through next season with a conditional player option for 2025, might not have waived his no-trade clause for any club but Houston. But his career numbers at Fenway Park — a 3.46 ERA in 75 1/3 innings, including two postseason appearances — probably would not have been a deterrent.