The device itself has been around for some time, delivering data with relation to heart rate and stress in the hope this can help protect against injuries. It also factors in how travel schedules can affect a player's fitness for the next game.
Read next: Best wearables for coaching
The decision to approve the Strap follows the company's trial with 200 minor league players continually using the device, which Whoop says gave it a chest of data to present to the league.
And according to ESPN, players also won't be required to wear the device, and can decide just how much information is shared by adjusting security settings.
But how exactly will this work for the players?
Well, in a blog post, Whoop CEO Will Ahmed indicated MLB clubs can now use the "Day Strain" metric to determine whether a pitcher is tired, instead of just tracking of how many pitches he's thrown during a game.
"Clubs could find out that player X is no longer effective when his Day Strain hits a certain number, regardless of whether he's thrown 50 pitches or 100 pitches to that point," he said.
Of course, this isn't the first time we've seen Whoop make waves in the professional sports scene. During last year's NBA season, then-Cleveland Cavaliers point guard Matthew Dellavedova was banned from strapping on the device after wearing it during 13 games.
While on the surface this would appear to be a trivial decision, it's actually the collective bargaining agreement between players and the NBA that states biometric monitors can only be worn during practice.
No such stipulation exists within baseball's highest tier, which will now offer players the choice to tap into their own data in order to potentially lead healthier careers.
How we test