While the major trade rumors in Major League Baseball (MLB) typically intensify in June, the approach of Memorial Day indicates an early look at potential storylines leading up to the trade deadline on July 31. To gauge the credibility of various trade rumors, Moneyline introduces a BS Meter, featuring four distinct levels: non-existent, low, medium, and high. This tool aims to help fans assess how much weight to give to reported insights regarding potential player moves without questioning the integrity of the reporters involved.

One notable rumor comes from MLB.com's Mark Feinsand, who reported that the Philadelphia Phillies had reached out to veteran relief pitcher David Robertson prior to the announcement of José Alvarado’s 80-game suspension for performance-enhancing drugs. While no serious negotiations were said to have occurred, the report carries a low BS Meter rating. Given the Phillies' current bullpen needs, precipitated by the loss of Alvarado, it is plausible that they expressed interest in Robertson, who is currently a free agent. Robertson had a solid performance with a 3.00 ERA and a 2.65 FIP while appearing in 68 games for the Texas Rangers last season. Even at 40 years old, his effectiveness raises questions about why he remains unsigned; factors could include his contract expectations or contemplation of retirement. Should he sign, it's expected that he would take about a month to prepare for a return to MLB play, though for which team that may be remains uncertain.

In another rumor, Bob Nightengale from USA Today reported that the Los Angeles Dodgers and Chicago Cubs are monitoring Colorado Rockies infielder Ryan McMahon, in case the Rockies decide to trade him. This discussion merits a high BS Meter designation due to the Rockies' inconsistent track record as sellers, even amidst disappointing performances. McMahon, a former All-Star, is currently hitting .211 with a .706 OPS, and while he excels defensively, concerns persist regarding his offensive output, especially with a contract that will pay him $32 million over the 2026 and 2027 seasons. The Rockies may be open to trading McMahon if they are willing to absorb some salary and accept a lower prospect return, but that approach could prompt them to retain one of their few high-profile players. The Dodgers' interest seems contingent upon their evaluation of Max Muncy’s slow start to the season.

Another significant rumor surfaced when Jon Heyman commented during a recent stream that the Pittsburgh Pirates are unlikely to trade pitcher Paul Skenes this summer. The BS Meter rating for this rumor is non-existent, as Skenes, at just 22 years old, represents a cornerstone of the Pirates' future. His track record of a 2.12 ERA over his initial 33 MLB starts provides ample justification for the Pirates to retain him as they seek to rebuild the team. Despite the organization's ongoing struggles, trading a player of Skenes' potential would be a misguided decision, as he embodies the type of talent the franchise should prioritize for long-term success. There could be a point in the future, as he approaches free agency, that a trade becomes more plausible, but currently, it is utterly unlikely.

Lastly, Nightengale also expressed the opinion that Rhys Hoskins would be an excellent fit for the Boston Red Sox if the Milwaukee Brewers opt to part ways with him. While this assertion is categorized as a low BS Meter rating and not an official report, it's easy to envision how Hoskins' power-hitting style might thrive in Fenway Park. However, the Brewers' position in the standings, currently sitting at 24-26, complicates potential trade scenarios. While the Brewers have shown a willingness to trade veterans, as seen in their transaction involving Josh Hader during the 2022 season, their decision to do so depends significantly on their situational context in the summer. Hoskins is rebounding with a .902 OPS after struggling in his comeback season, which could make him appealing to teams like the Red Sox seeking first base or designated hitter options.

In a separate insight during a B/R app stream, Heyman noted that the possibility of the Chicago White Sox trading Luis Robert Jr. hinges largely on his performance, suggesting that it would be unlikely if he were to continue struggling below a .200 batting average. His current contract, while previously considered team-friendly, now raises questions due to his injury history and recent performance dip, where he is batting just .210 with 19 home runs. Teams may view him as a rental player and might be disinclined to surrender significant prospects for him, especially if he were to decline his $20 million club option for 2026 in favor of a $2 million buyout.