Jonah Heim Is Heating Up — And Nobody's Paying Attention
Jonah Heim just posted a .365 wOBA over the last seven days against a dismal .208 mark over the prior 30 days. That's a 76% jump in offensive production at a position where the waiver wire is a wasteland. At 3% rostered with zero ownership movement, this signal is flying completely under the radar.
The Rolling Window Tells the Story
Heim's recent surge isn't subtle. Over the last 7 days: .312 AVG, 1 HR, a .365 wOBA, and a 17.6% strikeout rate across 17 plate appearances. Zoom out to 14 days and the numbers get muddied by the cold stretch — .161 AVG, .223 wOBA — but the Statcast data across that same window is what makes this interesting. His hard-hit rate sits at 58.3% and his exit velocity is 92.8 mph over both the 7-day and 14-day windows. The quality of contact didn't change; the results just started catching up.
Now compare that to his 30-day numbers: 42.6% hard-hit rate, 89 mph exit velocity, .141 AVG, .208 wOBA across 87 plate appearances. The last week represents a legitimate mechanical or approach shift — not just a couple of bloop singles falling in. You don't jump from 89 mph exit velocity to 92.8 mph on luck. That's a physical change in how the bat is meeting the ball.
Skills Validation: The Data Is Clear
A 58.3% hard-hit rate paired with 92.8 mph exit velocity from a catcher is strong. The strikeout rate has also ticked down — 17.6% over the last 7 days compared to 18.4% over 30 days. That's a modest improvement, but combined with the batted-ball quality spike, it paints a picture of a hitter who's locked in rather than getting lucky. With 34 plate appearances over the 14-day window, this is a solid sample — enough to take seriously, enough to act on.
WaiverScout Has Been Tracking This
We've had eyes on Heim since April. He first appeared on our radar as a Watch back on April 22 at 0% rostered. We upgraded him to Add Now on August 1 when his ownership sat at 6%, and he's bounced between classifications as his production has ebbed and flowed. Just a week ago, on August 23, we had him classified as Deprioritize. The new batted-ball data changed the calculus. This is exactly what the algorithm is designed to catch — the moment when a player's underlying skills inflect before the box scores fully reflect it.
No major fantasy outlet is talking about Heim right now. This signal is ahead of the mainstream conversation, which means there's still a window to act before an ownership spike.
Ownership Context
At 3% rostered with stable velocity, Heim is a free pickup in virtually every league format. If you're streaming catchers or stuck with a backstop hitting .200, the opportunity cost here is essentially zero. For context, other available catchers like Hunter Goodman, Gabriel Moreno, and Carter Jensen are worth monitoring, but Heim's batted-ball data over the last two weeks stands out.
Verdict: Watch
Jonah Heim is a Watch. The exit velocity jump from 89 mph to 92.8 mph is real. The hard-hit rate surge from 42.6% to 58.3% is real. The .365 wOBA over the last seven days is backed by quality contact, not fluke sequencing. But this is still a one-week hot stretch emerging from a brutal 30-day slump, and we need to see if the batted-ball improvements hold through another 20-30 plate appearances. Add him to your watchlist now. If the hard-hit metrics sustain through the next week, this becomes an Add Now — and by then, he won't be sitting at 3% rostered.