Photo Jake Stephens/Nats.Talk

When the Washington Nationals acquired the southpaw, Foster Griffin, from Japan, a lot of fans were left scratching their heads as to why the team would add him as their first starting pitcher acquisition of the offseason. In foresight, we liked the deal because recent data on the first year back for former MLB pitchers returning from Asia have had good results. In hindsight, we are loving the signing as the Nats are 10-3 in Griffin starts.

Look at Miles Mikolas (2018) as he came back from Japan and became an All-Star and Cy Young candidate. There are several immediate success stories and coincidentally include last night’s pitcher for Arizona, Merrill Kelly, who pitched in Korea. Some would say those Asian/MLB retreads have diminishing returns years after they return. But much of that is based on age. Kelly is now 37 and was drafted in 2007.

Griffin left MLB as a failed reliever after the 2022 season and returned as a starter with a 7-pitch repertoire. And he could be a star if he can consistently throw his cutter with enough horizontal movement. Last night, Griffin said it was his splitter that he just retooled with a grip that he used in Japan.

In last night’s game, Griffin threw the splitter a season-high 16 percent of the time in his abbreviated start due to back pain he left after 5.0 innings albeit he did have a double-digit lead. His spin rate on the splitter was 1,492 compared to his season average of 1,229, a difference of 263. He had a 50 percent swing and miss rate with the pitch in Friday’s game.

As you analyze Griffin, he is the epitome of a pitcher who will finesse you, and he admitted that “I’m not a guy who will throw 95.” And that means he doesn’t have the big fastball. What he has is a full arsenal of pitches — and when he tunnels them well — hitters are guessing at the movement on the baseball. He pivoted to throwing seven pitches to right-handed batters, and he throws six pitches to lefties as they see his full pitch mix sans the changeup.

Griffin has been so good that if you remove that blow-up game in Cincinnati where he gave up 9-earnies in just 4 1/3 innings, his ERA is 2.66 for the season versus his real ERA that is still good at 3.63. Griffin’s manager, Blake Butera, made Griffin wear it in that game in Cincinnati when he clearly was off his game and in his previous start pitched a career-high 103 pitches over 7.0 innings in Miami. Shoving pitchers usually backfires.

From Baseball Savant this season:

While the traditional WAR rankings won’t favor Griffin based on FIP (fielding independent pitching) which dings pitchers who aren’t high strikeout pitchers, Griffin has led his team to a 7-2 record and the team as aforementioned is 10-3 in his 13 starts. He has pitched against some of the best teams in baseball — and his first five starts were against either 2025 playoff teams — or teams that were current division leaders. In order, he faced the Phillies, Dodgers, Brewers, Pirates, and Braves.

If you go by WAR based on ERA, Griffin is the top pitcher on the Nats at a +1.1 WAR. Results matter, and some would say his numbers will never stand-up because of his 4.85 FIP versus his 3.63 ERA. But the point is that with his 7-pitch mix, batters aren’t able to square him up with consistency.

What Griffin does well is induce enough weak contact to stay viable. The opposition has a .208 and .154 batting average this season against Griffin’s sinker and changeup respectively. They are only hitting .200 and .120 respectively against his split-finger and curveball. The pitch that has been hit most often for power is his cutter with a .512 SLG. That pitch needs work because batters have hit him for a .256 batting average on that pitch with that SLG. Truth be told, that is a huge improvement since the beginning of his season.

Yes, results matter. Consistency of good results will determine how Griffin’s season and future goes. Certainly when the offense scores 14 runs for you, that helps, and that 14-1 win sure feels good as Griffin was the stopper last night and quickly snuffed out that three game losing streak and got the Nats back to .500 on the season. The lefty has done his part, now it’s up to his teammates to go on a long winning streak and prove that they are a potential contender.

If Griffin’s back is good to go, he is scheduled to pitch the finale in San Francisco on Wednesday before the team flies back to Washington, D.C. for a day-off on Thursday ahead of a series against the Mariners.