Will the Mariners Beat Oakland in 2023?

Oakland Athletics v Seattle Mariners
Oakland Athletics v Seattle Mariners / Steph Chambers/GettyImages

In short, I think the answer is “Yes, the Mariners will beat Oakland in 2023.” In this article, I look at how the Oakland batters stack up with the Mariners’ pitchers and vice versa. Thank you to Baseball Savant and ESPN Baseball stats for the data used here. You will also see that Logan Gilbert heard my prayer that one of our starting pitchers develop a splitter.

Mariners Matchup: Seattle Pitchers and Oakland Batters

I am working with a five-person rotation for the Mariners, but Spring Training and the first month of the regular season will likely shed more light on this. My five are Robbie Ray, Luis Castillo, Logan Gilbert, Marco Gonzales, and George Kirby.

In this group, Ray and Gonzales pitch with their left hands and the other three are righties. In looking at their OPS (batting plus slugging percentage), fewer batters hit pitches in 2022 when Ray, Kirby, and Gilbert pitched to left-handed batters. Fewer batters hit pitches when Castillo and Gonzales threw to right-handed batters.

In my anticipated lineup for the Athletics, there are four who bat better against right-handed pitchers and four who bat more successfully against lefties.

Since Oakland’s batters are split as to which type of pitcher they prefer and the Mariners have almost the same number of right-handed and left-handed pitchers, this information does not reveal an advantage to either team.

Mariners Matchup: Oakland Pitchers and Seattle Batters

According to Oakland’s Depth Chart Roster on February 9, there are eight pitchers in the starting rotation. Because Shintataro Fujinami recently arrived from Japan and has no MLB statistics, we will look at the other seven.

Oakland has five right-handed pitchers (RHP) and three left-handed pitchers (LHP), including Fujinami. What is interesting is that except for two pitchers who pitched equally well to left-handed and right-handed batters, the rest pitched better in 2022 to left-handed batters. This works for Seattle because the Mariners have several right-handed batters and two switch hitters.

On the batting side, Ty France (R/R), J.P. Crawford (L/R), Julio Rodriguez (R/R), Cal Raleigh (S/R) and Dylan Moore(R/R) bat equally well against right and left-handed pitchers.

Geno Suarez (R/R), Teoscar Hernandez (R/R), Sam Haggerty (S/R), and A. J. Pollock (R/R) hit more balls with left-handed pitchers.

Jarred Kelenic (L/L), Taylor Tremmell, (L/L) and Kolten Wong (L/R) hit more balls with right-handed pitchers.

The Mariners have enough right-handed players that they could make a lineup out of right-handed and split batters to give the Athletics’ pitchers a disadvantage.

Mariners: WAR (Wins Above Replacement)

I did go through the various pitches that our pitchers threw and the types of pitches the Oakland hit (as well as the Oakland pitchers and the Seattle batters) but I found that I was not gaining any real insights from this exercise.

I started looking at the STEAMER projected WARs to compare the statistics for Oakland and Seattle. There are several statistic formulas used to try and project the performance of pitchers and batters in the upcoming season.

FanGraphs describes WAR (Wins Above Replacement) as a statistic to capture a player’s total contribution to their team in one number. Julio Rodriguez has a WAR of 5.7. Since these numbers are not precise, we can estimate that Julio’s WAR in 2023 will be between 4.7 and 6.7. Luis Castillo has a projected WAR for 2023 of 3.5. The estimate would be that Castillo would likely have between a 2.5 and 4.5 WAR.

The WAR from FanGraphs translates to wins. So, if Luis Castillo became injured, and the Mariners had to replace him, the Mariners would likely lose 3.5 more games than they would have won with Castillo on the mound. This could vary, of course, for many factors, including the projected WAR of his replacement. (For more about WAR, see FanGraphs' glossary.)

Using the WAR numbers for our five starting pitchers added together, I came up with 11 WAR total. When I did the same for the top five pitchers listed for Oakland, I had a sum of 6.2 WAR.  The Mariners pitchers, according to WAR calculations should pitch better from the mound than the Athletics pitchers.

I did the same with nine position players who would hit for the Mariners. My total for the Mariners was 23.5. My total for the Athletics’ top nine was 13.6. Here again, the Mariners’ batting should be better than the Athletics batting.

Mariners vs Athletics: Observations

As I looked at the Astros, Angels, Athletics, and Rangers statistics, I started thinking that it would be great if one or more of the Mariners’ starting pitchers developed a splitter, but I did not know what that would involve. Baseball Savant shows which type of pitch caused batters the most strikeouts in 2023. Five of the Mariners’ batters had the greatest number of strikeouts against splitters, and I kept seeing the trouble batters had with splitters for the other teams.

I saw today, Valentine’s Day, that Logan Gilbert has developed a splitter: more reasons to love and admire Gilbert! This move might encourage other starters to throw this pitch... like Robbie Ray, who has reportedly added it as well! Starting pitchers with splitters would give the Mariners a real advantage!