MLB Bullpen Betting Systems Update for May 12

MLB Bullpen Betting Systems Update for May 12:

I’m here to post another MLB Bullpen Systems update for the week beginning Monday, 5/12, and we are coming off perhaps our best week overall this young season. Essentially every one of our systems advanced its record positively, highlighted by huge weeks for our new Importance of pitching system and those involving streaks. We also had a lot of movement this past week from individual teams, as the likes of formerly highly-rated bullpens like San Diego and New York struggled, while Boston and Minnesota climbed. Oh, and the team I pointed out last week, the Angels, continued to crater. There’s a lot to unpack, so let’s get right to it.

Following up on the feature story of last week, when I introduced a new system that I will be tracking going forward, the IMPORTANCE OF PITCHING SYSTEM hit it big last week, going 10-2 for just shy of +8 units profit. Hopefully, you caught last week’s update, or at least the daily Analytics Reports, and rode that wave. The system is now up to 25.7% ROI for the season. Recall that it has proven to be a nice edge when teams with lesser records have both the starting pitching and bullpen edges. 

The pitching system is our best-performing angle so far, but the better bullpen teams looking to thwart losing streaks angle is also performing quite well, nearly 24% ROI. Plus, our better bullpen underdog angles are on nice winning streaks, approaching a point in the season where they typically fare well once teams have settled in. With so much going right to this point, it looks like it could be a rewarding summer for people who share my belief that betting teams with better bullpens consistently is a solid strategy.

Speaking of which. I have always embraced the idea that better bullpen teams are the stronger wager when assessing the options. They just aren’t accounted for as much as starting pitching by oddsmakers, thus giving bettors value in typically at least 1/3 of games or more.

What’s the easiest way to use these bullpen ratings? Well, there can be more profitable ways (by ROI) requiring fewer plays, but the easiest method I have now is detailed in the very first system below. I have called it fittingly THE EASIEST WAY TO PLAY THE BULLPEN SYSTEM. By simply taking the better-rated bullpen team on my scale and avoiding those -190 or higher favorites that weren’t at least 19% better in winning percentage than the opponent, you would have netted +45.66 units in the 2023 season. It lost about twice that last season, so I’ve been hoping for a bounce-back year in 2025. We could be on our way to getting that.

Remember, to fully implement these strategies into your daily baseball betting routine, you only need two things: 1) the details of the systems as noted below and 2) VSiN Pro Access to MAKINEN DAILY POWER RATINGS page under the MLB tab on VSiN.com. You can also have the work of qualifying the angles done for you in our latest VSiN feature called the MLB Analytics Report. No serious baseball bettor should be without it. 

Now, here is an update of the various system records with results through Sunday, 5/11:

The quickest way to play the bullpen system
For the 2025 season, better rated bullpen teams that were not favorites of -190 or higher, or were -190 or higher and had a winning percentage 19% or higher and a starting pitcher edge of at least 20 have gone 292-239 for +15.24 units and a ROI of 2.9% so far in the regular season. This is a solid early return for what has been a long-running strategy I have embraced, especially when you consider that the average bettor playing every MLB game this season theoretically would be down almost -30 units.

We had a nice week overall, pulling in +5.88 units, but even still, there are bettors who prefer narrowing down the plays and using greater discernment in their baseball wagering to provide for even bigger edges. This is one of the main reasons we produce such a multi-faceted Analytics Report each day. Part of that report is the MLB Bullpen Systems you’ll see below. I personally am still playing these on a daily basis, and as you can see, they are still faring well.

** NEW 2025 IMPORTANCE OF PITCHING SYSTEM, BULLPEN AND STARTER **

BACK teams with both a better SM bullpen rating AND starting pitcher rating if that team has an even or worse record
In the 2025 season, I have found that teams with an even or worse record on the season but showing a better Steve Makinen Bullpen Rating AND starting pitcher rating have gone 63-31 for +24.19 units, and an ROI of 25.7%! To ensure this isn’t a fluke run, I went back and tabulated the results from the 2024 full regular teams, and teams in that same scenario were 189-127 for +35 units and an ROI of 11.1%. This seems to be a good foundational angle to follow since the prices aren’t that high typically, and we will be including it on the daily MLB Analytics Reports going forward. 

Fade better bullpen overpriced favorites of -190 or higher when the win percentage difference between teams is <19%
In the last two regular seasons in which the team with the Steve Makinen better rated bullpen was listed as a favorite of -190 or higher and had a winning percentage less than 19% higher than the opponent, that team has owned a 307-182 record, but for -118.22 units. This represented an ROI of -24.2%! For ’25, these teams remain off to an uncustomary good start, 30-7 for +13.5 units. This remains a crazy winning year for this angle, I don’t expect it to keep up for long. 

Back big favorites (-190 or more) with better bullpen ratings and winning percentage >=19% higher than the opponent
A 2023 mid-season bullpen ratings discovery found that some big favorites do prove worthy of backing consistently, regardless of the high prices, because the games are absolute mismatches. The last two regular seasons for this system finished at a record of 252-103, for +8.01 units. The ROI on this angle was at +2.3% ROI. For 2025, these teams are off to a very strong start, 42-12 for +12.02 units, an ROI of 22.2%. 

Overpriced better bullpen without a big starting pitcher edge angle was the 2023 and 2024 regular seasons’ most lucrative system
In combining starting pitcher differences in looking at games with -190 favorites or higher, there was a huge opportunity to be selective in fading overpriced favorites. Specifically, when the starting pitcher difference between the better Steve Makinen rated bullpen team was less than 20, those big favorites have gone 160-122, but for -115.88 units in the 2023 and 2024 regular seasons. That represents an ROI of -41.1%, very solid results. So far in 2025, these teams are unusually positive, 36-11 for +9.75 units. However, this system remains just a few games away from going negative. 

Better bullpen underdog teams are typically solid wagers all season long
A frequent and profitable system in the 2023 season, and prior to that as well, arose when the team with the better SM Bullpen Ratings played as an underdog (or pick ’em). Money line underdog teams with better bullpen ratings for the last two seasons were 701-790, but for +46.27 units. The 2024 season was below standards historically (lost -26.45 units), and we will be looking for a bounce back in 2025, but the start has been slow, 98-126 for -12.63 units. However, we are off back-to-back winning weeks, so we will keep this system on the daily reports for now. 

Better bullpen underdog teams in -110 to +144 range have won nicely
Digging in deeper to the better bullpen underdog system above, when limiting the plays to those better bullpen underdogs (or pick ’ems) in the -110 to +144 range, those teams produced a 328-350 record, for +9.84 units (ROI 1.1%) in the full 2024 season. I believe this angle has a bit more merit than the overall bullpen underdog system in that the better bullpens figure to be the difference in games that are expected to be highly competitive. For 2025, these teams have struggled out of the gate, as they are 85-110 for -17.72 units. This is still a disappointment, but off back-to-back winning weeks. 

Worse bullpen teams usually struggle in extending winning streaks
I have found that fading teams with a lesser SM bullpen ratings that were looking to extend winning streaks is also a strong strategy. Over the last two regular seasons, on two-game winning streaks, the teams with worse Steve Makinen Bullpen Ratings in a matchup have gone 428-485 for -78.6 units, a ROI of -8.6%. For this year, they are 45-53 for -8.46 units (ROI -8.6%), and have dropped -19.59 units over the last five weeks. Worse bullpen teams on 3+ game winning streaks finished the last two regular seasons with a record of 186-218 for -29.23 units. The ROI on that system was -7.2%. This has been a very consistent angle, so this year’s results (25-25, +0.96 units) are uncharacteristic. 

Better bullpen teams are capable of building lengthy winning streaks
In conducting a study of teams with better bullpens on winning streaks in 2023, when looking at teams with better Steve Makinen Bullpen Ratings looking to extend three-game winning streaks, I tracked that those teams that went 241-168 for +11.33 units, a respectable ROI of 2.7%. For 2024, better bullpen teams on a 3-game winning streak went 200-187 for -64.18 units (-16.6% ROI). This was a massive one-year swing for this system, and it was removed from the Analytics Report. However, I am giving it a chance in 2025, and so far it is 59-43 for +2.3 units after a huge +8.75 unit week. It seems to have recovered from a slow start. 

Better bullpen teams thwart losing streaks
Better bullpen teams on 3+ game losing streaks have gone 231-159 for +40.34 units over the last two regular seasons, maintaining remarkable consistency as well. The ROI during that span has been 10.3%! For 2025, it is off to a fabulous start, 37-20 for +13.39 units, an ROI of 23.5%. 

Again, these simple angles that can be qualified each day by utilizing the MAKINEN DAILY RATINGS page on VSiN.com or easily found on the MLB Analytics Report. Keep in mind, the bullpen systems are just one small part of a very in-depth handicapping library available to readers.

Here are the updated key bullpen stats that have been accumulated so far to start the regular season, as well as my current Bullpen Power Ratings. 

Key Bullpen Stats (through games of Sunday, 5/11)

Top 5 Bullpen ERAs
1. SAN FRANCISCO: 2.53
2. DETROIT: 2.72
3. HOUSTON: 2.93
4. SAN DIEGO: 2.94
5. KANSAS CITY: 3.02 

Worst 5 Bullpen ERAs
30. WASHINGTON: 7.13
29. LA ANGELS: 6.94
28. ATHLETICS: 5.11
27. BALTIMORE: 5.06
26. MIAMI: 5.05 

Top 5 Bullpen WHIPs
1. SAN DIEGO: 1.08
2. SAN FRANCISCO: 1.09
3. DETROIT: 1.09
4. HOUSTON: 1.15
5. MINNESOTA: 1.15 

Worst 5 Bullpen WHIPs
30. WASHINGTON: 1.73
29. LA ANGELS: 1.71
28. BALTIMORE: 1.56
27. MIAMI: 1.54
26. ATHLETICS: 1.53

Top 5 Bullpen Ks/9 innings
1. TORONTO: 11.15
2. HOUSTON: 10.4
3. NY YANKEES: 9.84
4. ATHLETICS: 9.74
5. MINNESOTA: 9.7 

Worst 5 Bullpen Ks/9 innings
30. CHICAGO CUBS: 7.35
29. ST LOUIS: 7.38
28. SEATTLE: 7.5
27. KANSAS CITY: 7.59
26. PITTSBURGH: 7.79 

Top 5 Bullpen Last 7 Games WHIPs
1. MINNESOTA: 0.8
2. ST LOUIS: 1
3. BOSTON: 1.05
4. TEXAS: 1.07
5. ATLANTA: 1.09

Worst 5 Bullpen Last 7 Games WHIPs
30. NY YANKEES: 1.92
29. WASHINGTON: 1.84
28. LA ANGELS: 1.78
27. SAN DIEGO: 1.78
26. ATHLETICS: 1.75 

I use a manual process of analyzing daily box scores to build my Bullpen Power Ratings. In most cases, the end number is a reflection of the stats listed above, with great consideration also given to overall talent, injuries, and momentum.

Biggest Movers in SM Bullpen Power Ratings since Monday, 5/5:

Biggest upward movers (PR points)
1. BOSTON: +11 points
2. MINNESOTA: +9
3. ST LOUIS: +7
4. TORONTO: +5
4. MILWAUKEE: +5 

Biggest downward movers (PR points)
1. ATHLETICS: -13 points
2. WASHINGTON: -12
3. SAN DIEGO: -11
4. ARIZONA: -9
5. CLEVELAND: -8 

Steve’s Current Bullpen Ratings/Ranks (as of 5/12)

Rank – Team – Bullpen PR
1. ATLANTA: 26
2. SAN DIEGO: 22
3. HOUSTON: 2
4. MINNESOTA: 21
5. LA DODGERS: 20
6. SAN FRANCISCO: 20
7. DETROIT: 19
8. NY YANKEES: 16
9. TORONTO: 16
10. TAMPA BAY: 16
11. NY METS: 14
12. KANSAS CITY: 13
13. MILWAUKEE: 12
14. BOSTON: 9
15. TEXAS: 9
16. CLEVELAND: 9
17. BALTIMORE: 7
18. ARIZONA: 6
19. CINCINNATI: 6
20. PHILADELPHIA: 4
21. SEATTLE: 4
22. ST LOUIS: 4
23. CHICAGO CUBS: 0
24. ATHLETICS: -5
25. PITTSBURGH: -10
26. MIAMI: -12
27. CHICAGO WHITE SOX: -12
28. COLORADO: -13
29. LA ANGELS: -24
30. WASHINGTON: -25 

These are sorted first by bullpen ranking and then by overall team power rating. 

As we head into this week’s games, there are three teams on a 3+ game winning streaks (TOR, MIN, STL) and three teams on a 3+ game losing skids (SEA, WAS, SF).