For the 2021 MLB preseason, The Game Day has compiled 2021 Mariners Prop Bets, including Seattle Mariners Futures Odds & Picks. Additionally, we will go over some 2021 Mariners Team Props and Player Props. The Mariners finished the 2020 season third in the American League West with a 27-33 record.
- Odds provided by BetMGM and Unibet as of Friday, Mar. 19.
- Read our full 2021 MLB Preseason Betting Guide for tips, predictions and picks.
Seattle Mariners Futures Bets: 2021 Team & Player Props
Player Props & Futures
American League Rookie of the Year
- Jarred Kelenic (+650) (Unibet)
Kelenic is considered one of the best prospects in baseball, ranking fourth on MLB.com’s Top 100 prospects list coming into this season. This is a 21-year old, well-rounded hitter with a plus hit tool mixed with power and speed. Kelenic has a sweet swing with the ability to barrel the baseball. He can make an immediate impact for the Mariners with the upside to provide 20 home runs and double-digit stolen bases.
The risk with Kelenic is that the Mariners will likely keep him off the big-league roster for at least the first couple weeks to delay his service time, but this makes him a value at +650. He should still see 400-500 plate appearances, so playing time shouldn’t be too much of an issue. Kelenic could be the most talented prospect to play in the majors this year, making him worth the investment at these odds.
Make your 2021 Mariners Picks for Player Prop Bets and Team Prop wagers at one of our partner sportsbooks.