On Sunday, a new candidate arose for that slot, when Boston Globe columnist Alex Speier reported that the Kansas City Royals have declared 2024 All-Star left-hander Cole Ragans not “off limits” in trade talks.

But Speier also quoted Royals general manager J.J. Picollo specifying that “there would have to be a really big return” for Ragans, a 2016 Texas Rangers first-round draft pick out of North Florida Christian High School in Tallahassee.

“Though the Royals would prefer a right-handed hitting outfielder, they won’t be tethered to the notion — making their considerable interest in Red Sox outfielder Jarren Duran at the trade deadline notable,” Speier added. Duran is a left-handed swinger.

Would Duran constitute a “really big return” for Ragans, who just signed a three-year, $13.25 million contract extension with Kansas City in February? If not, Beyond the Monster executive editor Ed Hand on Monday proposed adding left-handed hurler Kyle Harrison — acquired by the Red Sox from the San Francisco Giants as part of the stunning June 15 trade that sent Rafael Devers to the Bay Area.

“Royals get a controllable, All-Star-caliber outfielder who can cause mayhem on the bases with (Bobby Witt Jr.) as well as a lefty starting pitcher with a terrific pedigree,” Hand wrote. “Red Sox get a legit top-of-the-rotation arm with an affordable contract coming off a down year.”

According to The Athletic, Harrison — the Giants’ third-round pick in 2020 — “was once the best left-handed pitching prospect in baseball, give or take.” At the time of the Devers trade that sent the 24-year-old to the Red Sox, “his stock was back to where it should have been. He was already a quality starting pitcher, and his ceiling was much higher.”

After spending most of his time with Boston at Triple-A Worcester, Harrison made two starts plus a relief appearance for the Red Sox this year, allowing four earned runs in 12 innings with 13 strikeouts and five walks.

As for Ragans, he earned his contract extension with a 2024 season that saw him post a solid 3.14 ERA in 32 starts. But this season he missed three months with a strained rotator cuff, limiting him to just 13 starts with an unspectacular 4.67 ERA.

Ragans was slow to rise through the Rangers’ farm system. After spending his first two professional years in short-season rookie ball and Low-A leagues, Ragans underwent Tommy John surgery, costing him both the 2018 and 2019 seasons. The 2020 minor league season was then wiped out by the COVID-19 pandemic.

In June 2023, the Rangers traded Ragans to the Royals as part of a deal that brought closer Aroldis Chapman to Texas. Were Ragans to join the Red Sox, he would become teammates with Chapman, now the Boston closer.