Three MLB players whose trade value has plummeted since Opening Day

The good news for Alcantara is that his average fastball velocity remains in the upper echelon, per Baseball Savant. However, his expected ERA still sits at an unsightly 6.39, which means we shouldn't expect drastically better results soon. 

And for a Marlins team that, while young and scrappy, is expected to sell again this July, this isn't a great development for one of its most attractive trade chips.

2. RHP Ryan Helsley, St. Louis Cardinals

Relief pitcher is arguably the most volatile position in all of sports, since their output each season can vary from elite to middling or even downright poor. 

Helsley has found himself more in the "middling" category thus far in 2025, with a 3.60 ERA over his first 10 appearances out of the St. Louis Cardinals' bullpen. 

The veteran closer, typically one of the most dominant in MLB, has experienced a sharp decline in strikeout rate, while also walking hitters at an alarming 18.2 percent clip despite top-tier fastball velocity. That's leading to an expected ERA of 4.19, which is a far cry from his career ERA of 2.66. 

Helsley's most recent outing against the Milwaukee Brewers saw him surrender two earned runs in an inning of work. 

The Cardinals are also expected to sell this summer, with the 30-year-old Helsley posing as an obvious trade candidate given his closing experience and status as an impending free agent. But if Helsley keeps pitching like this, St. Louis might not get the prospect return it would like.

3. 3B Ryan McMahon, Colorado Rockies

The Rockies are downright abysmal, maybe even historically so. Could this be the season they finally engage in a real teardown at the trade deadline?

If so, McMahon is not forwarding that cause.

The 30-year-old, long thought to be a clear trade chip for Colorado, has a revolting .522 OPS over his first 99 at-bats of 2025 despite playing his home games at hitter-friendly Coors Field. And the underlying metrics don't favor a rebound soon: his expected batting average is just .174, compared to his current mark of .152. 

He's also striking out almost 34 percent of the time, and while he's hitting the ball hard (average exit velocity of 93.4 miles per hour), it doesn't matter if there's no reason for a pitcher to throw McMahon a strike.

Of course, this could all be moot if the Rockies decide to stand pat this summer. But in terms of the player, his case to be traded seems to be weakening.