MLB Best Bets Today May 21

There is a lot of getaway day action on the docket for Wednesday, as six games have morning start times for us here at the VSiN headquarters. Two more start in the Noon hour, so it’s the type of day where you want to look at the daytime weather conditions and see if a boost for bats is in order.

We do have some really good pitchers on the evening slate and some others that are maybe a little bit questionable, leading to a few bigger moneyline prices.

This article will run Monday-Saturday and I’ll write up a standalone preview for Sunday Night Baseball on Sundays. This year, we’ll also have MLB best bets from Greg Peterson posted with overnight lines.

My tracking sheet is here. For transparency sake, I also have tracking for my three MLB seasons at VSiN (2024, 2023, 2022).

Odds are from DraftKings Sportsbook because they are widely available to readers and because of some of our betting tools. I highly, highly, highly encourage you to shop around for the best lines. Sometimes they will be at DK. Oftentimes, they will not. Do what you can to shop around and get as much bang for your buck as possible.

Feel free to use my opinions and thoughts, as well as our suite of MLB Betting Tools, including the DraftKings and Circa Betting Splits, Steve Makinen’s Daily Ratings, Greg Peterson’s Daily Lines, the 1st 5 Innings Analyzer, and Umpire Stats.

Here are the MLB best bets today for May 21:

New York Mets at Boston Red Sox (-148, 8)

6:45 p.m. ET

The slumping Mets have to try to conquer Garrett Crochet tonight, which is no easy task. The Red Sox draw Tylor Megill, who has had a rough go of it lately, so we’ll see if he can right the ship and keep his team in the ballgame against a real tough customer.

I’m looking at a couple of Red Sox player props here. Let’s start with Alex Bregman Hits + Runs + RBI Over 1.5 at -135. Megill has had some reverse platoon splits this season in terms of his results. Righties own a .270/.347/.382 slash with a .326 wOBA against him to this point. Bregman has been terrific in righty vs. righty matchups with a .286/.354/.585 slash and a .399 wOBA over 164 plate appearances. He only has a 17.1% K% in that split, which is the best of any Red Sox regular. 

Next is Wilyer Abreu Over 0.5 Walks at +130. Abreu has an 11.3% BB% against RHP, as he’s drawn 18 walks in 159 PA thus far. Megill has issued a walk in 13% of his plate appearances against lefties this season. While he’s mostly taken the sting out of their bats with a .182 BA and a .234 SLG against, he’s been very careful with them. Megill has walked 10 batters in just 62 plate appearances this month over 12.1 innings, so that’s a 16.1% BB% in three May outings. He also walked four against the Phillies in his April 21 start.

In 28 plate appearances against lefties over those three May starts, Megill has a 21.4% BB%. It is a small sample size, but Fenway Park is a daunting venue and Abreu has exercised some good patience against righties.

Picks: Alex Bregman (BOS) Over 1.5 H+R+RBI (-135); Wilyer Abreu (BOS) Over 0.5 Walks (+130)

Philadelphia Phillies (-218, 11.5) at Colorado Rockies

8:40 p.m. ET

Taijuan Walker and Carson Palmquist are the listed starters for this one at Coors Field. This is a one-sided handicap for me, as I’m looking at the Phillies lineup against Palmquist. I actually backed Palmquist in a way in his MLB debut, as I had the 1st 5 Under and the full-game Under against the Diamondbacks. Corbin Burnes did all the heavy lifting there to cash both tickets, as Palmquist gave up five runs on six hits in four innings.

He had zero swings and misses on pitches in the zone and that’s a huge problem facing the Phillies. Over the last 14 days, the Phillies are second in wOBA against lefties at .399 and second in wRC+ at 155. The Diamondbacks are fifth, for what it’s worth. Philadelphia has a 16.3% K% and a 10.2% BB% in that span, which is rather remarkable. Usually when you draw walks, strikeouts come with it because of the deep counts. But, the Phillies are clearly not chasing much outside the zone and are making contact if they do.

From a contact quality standpoint, Palmquist got a little unlucky in that start against Arizona, but that’s precisely what not generating Whiffs will do. He also allowed a 55.6% Pull%. He was 86.8% sinker/slider in that start, so he didn’t mix his pitches well. And, oddly enough, Statcast at the MLB level classified what was a four-seam fastball in the minors as a sinker at the MLB level.

So, we’ll see about that, but the Phillies are very dangerous when making contact and they make a lot of it. Add in a very spacious outfield at Coors and I don’t see a reversal of fortunes for Palmquist.

Pick: Phillies 1st 5 Team Total Over 3.5 (+100)

Los Angeles Angels at Sacramento Athletics (-175, 10.5)

10:05 p.m. ET

The Angels and the Athletics play on a warm evening in Sacramento with first-pitch temps in the mid-80s. That could make for a good night for offense, but the Angels have really had a hard time with lefties and they get one here in JP Sears. The A’s, meanwhile, get to go up against Jack Kochanowicz.

I’m looking at Sears and this matchup against the Angels because it should really suit him well. The Angels have the second-highest K% against LHP this season at 28% and have the lowest BB% at 3.9%. They are batting .193/.235/.349 in that split with a .254 wOBA and a 59 wRC+. Only Baltimore is worse in wOBA and only Baltimore and Colorado are worse by wRC+.

Sears, who enters with a 3.31 ERA, 3.61 xERA, and a 3.93 FIP is a strike-thrower through and through, as he has just a 5.0% BB%. He doesn’t generate a lot of strikeouts with an 18.8% K%, but this matchup gives him not only more upside in that category, but also should allow him to work deep into the game based on his pitch efficiency.

Sears has also scaled his Barrel% back from 11.1% in 2023 and 10% in 2024 to 7.3% this season. Increased slider usage has been a big part of the equation. By Statcast pitch type values, the Angels are -11.4 batting runs against sliders. They are also -9.4 batted runs against changeups, which is the second-worst mark in the league. Sears has cut back his changeup usage a little bit this season, but this matchup should call for more of them. I like Sears Over 4.5 Strikeouts at plus money here.

Kochanowicz has had good results in his last two starts, but a lot of smoke and mirrors, too. He allowed one run over 6.2 innings to the Dodgers and one run over 5.2 innings to the Orioles, but he walked four in both starts and had Hard Hit% marks of 68.8% and 53.3%. He’s allowed a 48.4% Hard Hit% this season, but has somehow run a .293 BABIP and a 74% LOB% with his 13.7% K%. When those things normalize, his 10.4% BB% will be even worse.

I’m just not a believer in the profile at all. He has a 5.7% K% with men on base, but has allowed just a .239 BABIP. He has a 4.4% K% with RISP, but has allowed just a .200 BABIP. Given all the hard contact he allows, those BABIPs are incredibly unsustainable. And a K% that low means he shouldn’t be stranding so many runners.

Along with Sears Over his K prop, I’m looking at the A’s for the 1st 5 Run Line.

Picks: Athletics 1st 5 Run Line -0.5 (-120); JP Sears (ATH) Over 4.5 Strikeouts (+110)