What’s Working, What’s Not Been Working For The 2023 Seattle Mariners

Fresh off of their first playoff appearance since 2001, the Seattle Mariners’ fan base was locked and loaded for the 2023 season. The season has gotten off to a rocky start, with the team hovering around .500, but there is hope on the horizon to make the playoffs in back-to-back years. Let’s look at what’s working for them and what they need to improve.

The Mariners hoped to sure up their defense at second base by acquiring Kolten Wong this offseason. While the former Gold Glover was one of the worst defensive second basemen last year, the Mariners hoped he would regain his form. While he’s been an average defensive second baseman (52nd percentile in terms of Outs Above Average), his bat is non-existent. Among qualified hitters, Wong is last in Barrel %, Average Exit Velocity, and second to last in xSLG. How does this look in traditional stats? He’s batting .140 with a .371 OPS and a 10 OPS+. Combine the average defense and the worst bat in the league, and you have a league-worst -0.9 WAR. 

What can the Mariners do with this? Not much at the moment. They do feature veteran Tommy La Stella, who’s played plenty of second base, but he was not known for his defense at all. Dylan Moore seems to be the shoo-in for the position, but he’s struggling with an oblique strain that is sidelining him longer than expected. What they can do is weather the storm until Moore comes back. He at least provides a pop in his bat with good defense.

They’re also missing a valid DH. Regarding WAR at the DH position (which is just hitting), the Mariners rank last, and for a good reason. The DH has featured three people, Cooper Hummel, AJ Pollock, and Tommy La Stella. Between those three guys, La Stella features the best OPS+ at a paltry 53. They can search any of the teams in the majors for a bat. Take the Pirates as an example. They picked up Andrew McCutchen and former Mariners’ great Carlos Santana for cheap this offseason, and I’m sure around the trade deadline, they’ll be plenty of teams offloading veteran hitters. 

What’s been working is the pitching for the team. Luis Castillo spearheads the above-average rotation this year and hasn’t disappointed, amassing 34 strikeouts in 29.2 innings pitched. His ERA+ is 278 (the average pitcher is 100), and his FIP is a beautiful 1.64. For a reference to FIP or Fielding Independent Pitching, the best season ever by a starting pitcher was Pedro Martinez in 1999, finishing the year at 1.39. There is a slight setback in the rotation because Robbie Ray was ruled out for the remainder of the season due to flexor tendon surgery. Chris Flexen was the pitcher that took over that additional spot in the rotation, but he hasn’t performed nearly as well, sporting an 8.86 ERA in four starts. 

The bullpen has been tremendous as well. Veteran Paul Sewald is handling the closing duties this year, already gathering seven saves thus far. Matt Brash has stepped up in the absence of Andrés Muñoz, doing his best impersonation of him by collecting 22 strikeouts in only 10.2 innings. This pitching staff will only improve with the return of Muñoz. 

If the Mariners can get some offensive production out of their second base spot and DH, you are looking at a dangerous playoff team. The Mariners are banking on Dylan Moore’s return and maybe a pickup at the trade deadline. Pitching-wise, they’re one of the best in the league talent-wise. When it comes to the end of the games, opposing teams will struggle to score against Brash, Muñoz, and Sewald. Regardless, we can all agree we’re glad to have baseball back!