When Will the A's Call Up Leo De Vries? - Latest Odds
Leo De Vries MLB Debut Date: Latest Odds
If you're an MLB fan or a baseball bettor and you haven't yet heard of Leo De Vries, that's about to change. The 19-year-old switch-hitting shortstop is the A's top prospect in their entire system and currently ranks second overall in MLB Pipeline's list of top 100 prospects in the game.
De Vries was originally signed in 2024 by the Padres — coincidentally as a second-ranked prospect then, too, ranking behind only Roki Sasaki as the best international prospects available in that signing period. How did he end up in the A's system? De Vries was the headline trade piece sent from San Diego to acquire closer Mason Miller, who remains one of the best relief pitchers in the sport.
De Vries has inarguably been a great return, showing an ability to do everything from hitting for power to playing great defense and stealing a ton of bags at every level. Just look at what he's done so far this season in double-A for the Midland RockHounds.
Statistics in Double-A Midland as of 8/5
- GP: 87
- AVG: .294
- OBP: .383
- SLG: .462
- HR: 13
- RBI: 49
- BB: 49
- SO: 84
- SB: 33
If you're looking to bet or trade on when De Vries makes his MLB debut, the first thing you should notice is that he's still in double-A at the time of this writing. And while teams do still promote players on rare occasions to their big-league roster from double-A, that teams to be for players who elevated their game in the offseason in order to break camp with their team.
So, what do the odds say about when De Vries is most likely to make his MLB debut?
Leo De Vries: Debut Date Odds
| Before Sep. 1, 2026 | 15% |
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| Before Oct. 1, 2026 | 26% |
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| Before Nov. 1, 2026 | 41% |
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| Before May 1, 2027 | 75% |
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| Before Nov. 1, 2027 | 94% |
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The A's currently currently aren't anywhere near playoff contention, so it's reasonable to wonder if they'd consider promoting De Vries to their big league club to get some experience as the clock runs out on the 2026 season. But as we mentioned previously, De Vries isn't likely to reach the show this season without first paying a visit to the org's triple-A affiliate in Las Vegas.
A more realistic assumption you could make is that De Vries is slated to make his MLB debut at some point in 2027, whether he breaks camp with the club or, more likely, gets his promotion mid-season in '27.
Want to make a trade on Leo De Vries' MLB debut date? This is how we see it: De Vries isn't going to make his debut in 2026, so we'd feel comfortable recommending the "No" markets on any dates this calendar year, though those will obviously provide a lower-value return.
Betting on De Vries to debut before May 1, 2027 currently has a 75% chance of hitting, per Kalshi, but that's a risky play, too. Why? While De Vries could very well get called up in April after a few weeks at triple-A, it's also just as likely that the 2027 MLB season doesn't begin on time due to team owners locking the players out while they negotiate a new CBA. If Opening Day is delayed even a couple weeks, that will greatly reduce De Vries' chances to make the big leagues by May 1.
In truth, the only markets we'd recommend trading on are the "No" markets on 2026 dates or the "Yes" before Nov. 1, 2027 market that's currently holding 94% odds to hit. If you want to make a riskier play for more value, go for it — you're a braver baseball fan than we are.
Mark is a lifelong sports fan who inherited rooting interests in the St. Louis Cardinals and Pittsburgh Steelers. After a decade in sports media covering sports betting as a writer, editor and producer, Mark brought his long track record of sports experience to the Sportsbooks Online team in early 2025.
