As Memorial Day approaches, the MLB trade rumor season begins to take shape, giving fans an early glimpse at potential storylines leading up to the trade deadline on July 31. To gauge the credibility of recent rumors, Moneyline has devised a BS Meter with four distinct settings: non-existent, low, medium, and high. This tool is intended to provide fans with insight into the likelihood of these rumors resulting in actual trades rather than questioning the credibility of the reporters.

One notable rumor comes from MLB.com's Mark Feinsand, who reported that the Philadelphia Phillies 'reached out' to pitcher David Robertson before the announcement of José Alvarado's 80-game suspension for performance-enhancing drugs. While Feinsand noted that 'no serious talks took place,' the report carries some weight. The Phillies, already in need of bullpen reinforcements prior to Alvarado's suspension, have a plausible motivation to pursue Robertson. Despite an impressive 3.00 ERA and 2.65 FIP during his tenure with the Texas Rangers last season, Robertson remains a free agent this late in the season, raising questions about his market value or potential reluctance to continue his career.

Another rumor, reported by Bob Nightengale of USA Today, suggests that the Los Angeles Dodgers and Chicago Cubs are keeping a close eye on Colorado Rockies infielder Ryan McMahon, possibly in preparation for a trade. This rumor is classified as high on the BS Meter due to the Rockies' historical resistance to being major sellers, even in the face of poor performance. McMahon, a former All-Star, is currently hitting .211 with a .706 OPS, which raises questions about the allure for interested teams. With a multi-year commitment of $32 million set to kick in between 2026 and 2027, it remains uncertain whether the Dodgers or Cubs would be enthusiastic about pursuing McMahon, particularly if the Rockies do not show a willingness to negotiate.

In a discussion on the prospects of the Pittsburgh Pirates parting ways with young talent Paul Skenes, Jon Heyman dismissed the idea entirely, indicating that there is 'no way, no how' that Skenes would be traded this summer. This assessment is deemed non-existent on the BS Meter, especially considering Skenes' status as a 22-year-old promising pitcher who is not eligible for arbitration until 2027 and free agency until after 2029. Despite the Pirates' struggles this season, moving a talent of Skenes' caliber would be counterintuitive to the franchise's long-term strategy. With a 2.12 ERA in his first 33 MLB starts, Skenes is viewed as a foundational player for the Pirates moving forward.

Nightengale also speculated that Rhys Hoskins could be a potential fit for the Boston Red Sox if the Milwaukee Brewers decide to sell. This opinion is rated low on the BS Meter, as it hinges more on potential than on substantiated reports. Hoskins, a power hitter, could thrive in Fenway Park; however, the Brewers' current performance complicates the likelihood of a trade. At 24-26, the Brewers remain within reach of a playoff spot. Nonetheless, their previous willingness to move veterans, as evidenced by the trade of Josh Hader in 2022, could lead to a scenario where Hoskins, who has rebounded from an injury this season with a .902 OPS, becomes available. The Red Sox and other teams may find appeal in acquiring Hoskins but would need to assess the Brewers' willingness to part with him.

Lastly, Heyman's remark regarding Luis Robert Jr. emphasized that a trade involving the outfielder would not occur while he is hitting below .200, at least not for a significant return. This insight also carries a non-existent rating on the BS Meter. Robert's contract, projected to be favorable, is currently under scrutiny as he faces challenges at the plate, batting just .210 with 19 home runs and a .630 OPS this season. Although Robert possesses remarkable speed with 17 stolen bases and offers defensive value, he may not attract the caliber of prospects that would justify a meaningful trade, particularly in light of his inconsistent performance.