MLB HR props for Thursday 9/21: The life of Riley

We've cashed only one home run prop three days into the week, so we're due to find a winner on this shortened slate. Here are my three favorite HR props for Thursday's MLB action. 

Austin Riley (+360 DraftKings)

Washington Nationals starter Jake Irvin has given up 20 home runs in 23 starts this season, and he hasn't even faced the Atlanta Braves yet. The most dangerous lineup in baseball will be foaming at the mouth to jump on the rookie early. Let's roll with Austin Riley, who's batting .304 with two home runs over the last two weeks and has cracked 26 of his 36 homers off right-handed pitching.

Nick Castellanos (+540 FanDuel)

All signs are pointing toward a big night for Nick Castellanos. For one, Castellanos leads the Philadelphia Phillies with five home runs over the last two weeks, including four over the last six games. The right fielder has also crushed left-handed pitching to the tune of eight homers, a .326 batting average and a .921 OPS. With lefty David Peterson scheduled to start for the New York Mets, let's roll with Castellanos.

Mookie Betts (+390 DK)

San Francisco Giants rookie Kyle Harrison has surrendered seven home runs in his first five MLB starts. The left-hander gets his first career crack at the Los Angeles Dodgers on Thursday night, and I can't imagine it will go very well for him. Mookie Betts leads the Dodgers with 14 home runs and a 1.132 OPS against lefties this season, and the wind will be blowing out to center field for him. The superstar outfielder has just one homer in his last 37 at-bats, but this is a perfect opportunity to get back on track.