Due to the bullpen collapse it will be mostly forgotten, but Foster Griffin had yet another rock solid start yesterday. He has been such an outstanding addition to the rotation, and signing him out of Japan has proven to be an outstanding deal for Paul Toboni. On the season, Griffin now has a 3.46 ERA in 78 innings.
While Mark understandably got ahead of himself assuming Griffin had an 8-2 record when the Nats got up by 8 runs, he has had a stellar season at 7-2. The Nats could not have asked for anymore when they signed Griffin on a 1-year $5.5 million deal this offseason.
Griffin was a first round pick by the Royals all the way back in 2014. However, the lefty struggled to meet first round expectations. He steadily climbed the ladder, but never truly stood out. In 2020 and 2022, Griffin had a couple cups of coffee in the big leagues, but was never able to stick. That is when he made the career changing decision to play in Japan.
He signed with the Yomiuri Giants, the most famous team in Japan. Griffin completely evolved as a pitcher while he was overseas. He had three outstanding seasons in Tokyo, posting a 2.57 ERA in 315.2 innings. Griffin also added a sinker, a sweeper and a splitter while he was in Japan. That gave him a 7 pitch mix that dominated in Japan, and after 2025, he wanted to see if it could dominate in the MLB.
Due to his lack of big velocity or flashy stuff, Griffin’s market was not overly lucrative. While teams lined up to give KBO star Cody Ponce multi-year deals, Griffin did not generate that kind of interest. Teams were willing to give him a flier though, and he ended up signing with the Nats, who gave him a spot in the rotation.
While analysts in the US did not give much thought to Griffin, those who follow the NPB closely felt the Nats got a steal. Yakyu Cosmo, who is a popular English language NPB outlet, said that Griffin’s deep mix and strong command made him bullish about MLB success. He also said that Griffin reminded him of Seth Lugo.
Griffin’s results and stuff have been very Seth Lugo like this season. He has a 3.46 ERA, and is slightly overperforming his underlying numbers. That is more or less what Lugo has done the past three seasons in Kansas City. Both use insanely deep arsenals to keep hitters off balance and deceive their way to success.
Having a deep pitch mix is en vogue these days, and Griffin is at the forefront of this revolution. Lance Brozdowski, an analyst I really enjoy, has been talking about starting pitchers increasing their mixes for years now. Griffin is one of those guys, and is able to have success despite none of his 7 pitches being elite.
Griffin’s craftiness makes him very fun to watch. He is able to mix and match at will and understands how his pitches play off of each other. Griffin does a great job tunneling all his pitches to give hitters as little time as possible to make a decision. Batters have to decide whether they are seeing a 4-seamer, a sinker, a cutter, a curve, a sweeper, a changeup or a splitter so quickly. A lot of those pitches look very similar out of the hand as well and then end up in completely different places.
This dilemma Griffin puts hitters into is a big reason why he has actually put up fairly strong strikeout totals. Griffin has 74 strikeouts in 78 innings, which is quite solid. You would not usually expect a guy who averaged 91.3 MPH on their fastball to have 8.54 K/9. However, that is exactly what Griffin is doing and it is because of how crafty he is.
There are some regression red flags here though. Griffin’s FIP sits at 4.75 and his xERA is 4.30. However, Griffin’s xFIP of 3.79 paints a more generous picture. A big reason as to why these numbers are high is because of how many home runs Griffin allows. He has given up 15 long balls on the season, and is allowing 1.73 HR/9. That has been the one Achilles heel in his game.
With Griffin’s mediocre stuff, he has to command the ball well. When he misses over the heart of the plate and the hitter guesses the right pitch, it tends to go far. I would expect Griffin to post an ERA around 4.00 from here on out, but even that would be overperforming pre-season expectations.
Paul Toboni only signed Griffin to a one-year deal, so he will have to make a decision on the lefty at the trade deadline. Griffin is likely to be a sought after rental in a market filled with pitching needy teams. However, if the Nats stay around .500 and in the Wild Card mix, it could create a bit of a dilemma.
If the Nats wanted to, they could offer Griffin a 3-year extension to try and keep him around. I tend to think that Griffin is likely to be moved at the deadline. If that is the case, it would be a bummer because I have really enjoyed watching him pitch. I would be very open to a Griffin reunion in the offseason as well.
Not every move Paul Toboni has made has worked out, but this one has been a complete win. Griffin has been a steady presence at the top of the Nats rotation and should provide value moving forward whether that is with the Nationals or in a trade.