We hit on two of the three props yesterday, as Brandon Belt’s dud kept us from a clean sweep of MLB player props over on Underdog Fantasy. There’s Major League Baseball action all day today, and honestly, what is better than that? While looking for some best bets and MLB player props of the day, you can also toss in some MLB DFS lineups! Before you get to setting your daily and seasonal fantasy baseball lineups, check out these free MLB player props and MLB daily picks on Underdog Fantasy for “Pick'Em” contests today. As always, we have plenty of tools for you to use, whether it be for your MLB bets or MLB DFS lineups, including our MLB weather report, our MLB lineups page, and our MLB daily projections. Without further ado, here are my favorite MLB picks of the day and top MLB player props over on Underdog Fantasy for May 21.


Yordan Alvarez, Houston Astros - OVER 1.5 Total Bases

When James Kaprielian takes the mound for the Oakland Athletics, sign me up for the opposing offense, please and thank you. The Oakland right-hander has a 9.30 ERA as a starter this season and overall when pitching on the road this season, he’s posted a 17.05 ERA and allowed a slash line of .406/.513/.813 against him! He has struggled to get left-handed hitters out, as lefties have slugged .712 against him, and lefties in particular have a 3.75 HR/9 against him. Alvares has a .902 OPS and 149 wRC+ at home this season, and against righties, we are talking about a .957 OPS, .276 ISO, and 165 wRC+. He’s a career .313 hitter against Oakland, to go along with a 1.068 OPS and a 9.9 AB/HR, and he’s slugging .630 over his last 12 games. Lastly, in the month of May, not only is he hitting .351 against right-handed pitching, but he has a 1.077 OPS, .297 ISO, 197 wRC+, and a 51.6 percent hard hit rate.

Yandy Diaz, Tampa Bay Rays - OVER 0.5 Singles

Diaz is in the midst of a 13-game hit streak where he’s slashing .367/.446/.694 and eight of his 18 hits have gone for extra bases. Today, all we need is a single, so that the hit streak stays alive, and we hit our over! For the 2023 season as a whole, Diaz has hit right-handed pitching at a .357 clip, and during his hit streak, nine of his 15 hits against right-handers have been singles. Freddy Peralta has some good stuff, but he has reverse splits, so right-handed hitters have hit him better, and he’s struggled from his home park, serving up a 7.16 ERA and .324 BAA across three starts on the road. Diaz loves facing righties, and loves hitting at home, so what more could we ask for than Diaz at home against a righty, and against a righty that doesn’t like pitching to righties on the road?

Vladimir Guerrero Jr.. Jr, Toronto Blue Jays - OVER 1.5 Total Bases

This is a pure gut call, as Vladdy hasn’t surpassed this line in any of his last four games, but that isn’t scaring me off today. Baltimore’s Dean Kremer has a 4.79 ERA and .321 BAA on the road this season, and right-handed hitters have posted a .462 SLG against him when Kremer is away from his home park. Kremer must hate seeing Guerrero Jr. come to the plate, seeing as the Toronto slugger is 6-for-16 with four home runs in his career against him., good for a 1.188 SLG and 1.632 OPS. Guerrero has a .511 SLG and .226 ISO versus right-handed pitching this season, and this matchup is exactly what the doctor ordered. 

Other Underdog Fantasy Player Props to Consider


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