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Your new pitcher Yusei Kikuchi

Who is Yusei Kikuchi?

The 27-year-old lefty tried to move to the States in 2009, when he was a senior at Hanamaki Higashi High School, in northeastern Japan’s Iwate Prefecture–graduating just before Shohei Ohtani entered as a freshman. The Pacific League’s Seibu Lions won his negotiating rights in a draft-day lottery when half of NPB’s 12 teams selected him as their first-round choice.

Kikuchi signed with Seibu, announcing his decision in a tearful press conference. Many in NPB have spoken in whispers about how the Lions strong-armed the youngster into staying in Japan.

“…he is aggressive with his fastball. He’s not trying to fool guys. Major league teams like to see that. They need to see that guys aren’t afraid to throw their fastball in the zone.”

The day before his posting, he appeared back in Hanamaki with two of his teammates to participate in an event, where he spoke of his upcoming challenge.

“I’m not going to be on an emotional roller coaster,” Kikuchi said about the posting according to Nikkan Sports. “The negotiating period is 30 days and a lot of unexpected things are likely to happen I suppose, so I’m going to train and prepare so that I can produce next season.”

When he first turned pro, Kikuchi’s first year was more or less wiped out by injury and he had an up-and-down NPB apprenticeship that largely consisted of managing shoulder stiffness and inflammation with one detour for elbow discomfort. Despite all that, he’s become one of NPB’s top pitchers–it just took him a little longer to get there.

What scouts say

In a poll I conducted this past year of major league scouts who cover NPB, Kikuchi was rated the fifth-best prospect of any player in Japan–including those who are not yet eligible to leave.

“He’s a left-handed power arm. What’s not to like about him? He’s developed control of his offspeed pitches and he is aggressive with his fastball. He’s not trying to fool guys. Major league teams like to see that. They need to see that guys aren’t afraid to throw their fastball in the zone.”

“Even in Japan, Kenta Maeda threw mostly sliders, and major league teams want to see more confidence in the fastball.”

“He used to always be missing something. He used to have a lot of things going on. He had a reputation as being injury-prone. But his body is a lot larger now (100 kg). He’s now confident in what he does. He appears more mature.”

To a man, the scouts see Kikuchi as a valuable middle-rotation starting pitcher.


Overall: Kikuchi is primarily a fastball-slider pitcher. He got swinging strikes on 12.2 percent of his pitches this year, fourth-most among pitchers throwing 90-plus innings. Hitters made below-average contact on his pitches in the zone, but he was No. 1 in terms of least contact out of the zone and well above average in getting batters to chase.

Fastball: Averaged 147.3 KPH this year. Kikuchi threw it about 49 percent of the time and got swinging strikes 9.6 percent of the time, the third-highest figure of pitchers throwing 1,000-plus fastballs this year. In 2017, it was arguably the best fastball in NPB.

Slider: Since the start of his pro career, the slider has gradually become Kikuchi’s big pitch, and is easily the best slider thrown by an NPB starting pitcher. This past year, 35 percent of Kikuchi’s pitches were sliders, the highest figure for anyone who threw 2,000-plus pitches. He locates it extremely well and got swinging strikes on 17.0 percent of his sliders – a shade behind the 17.1 posted by four-time PL strikeout leader Takahiro Norimoto, who lacks Kikuchi’s location.

Curve: Kikuchi’s No. 2 secondary pitch, thrown about 10 percent of the time. It’s not a great pitch, but like a lot of Japanese pitchers, he’ll throw it for strikes to get ahead in counts a few times in a game.

Change: Used about 5 percent of the time and it has been effective in limited applications. It’s a chase pitch, generally not thrown for strikes.

Others: A few of his pitches in 2017 were labeled splitters, and a few this past season were designated as two-seamers–depending on who you ask. It’s not unusual in Japan for MLB-bound players to play around with two-seamers. Kikuchi might also have tried it in 2017 when Seibu’s mound was reportedly made harder.

Where is he now?

In 2017, everything came together for Kikuchi. He was healthy the entire year, and was dominating the league, umpires flagged Kikuchi for his double-leg-pump pitching motion in August. It didn’t seem to bother him though, as he allowed just three runs over his last six starts of the season, (including one in the postseason) striking out 57 batters in 49 innings. He was named the PL’s pitcher of the month for September and October.

“I hated it that anyone might say I was getting people out because of that (illegal) delivery,” he said after winning the monthly honor.

This past May, Kikuchi dealt with a shoulder issue diagnosed as “degradation” of the shoulder that delayed recovery after his starts. He was deactivated from May 6 to June 1.

“It’s a concern of course,” one scout said about Kikuchi’s health and less-dominant results this year. “That’s where we scouts come in to see what he actually is doing.”

Another scout said, “Let’s see, he’s a lefty with great command of his slider who throws 92 miles per hour and throws strikes. I think somebody will be interested.”


The injury issue is a question mark because he will be throwing a different ball from harder mounds that put more stress on the knees than the somewhat softer NPB mounds he’s used to. He’s been hurt in the spring, and he’s going to go through a spring training that is quite different from what he’s used to.

The less-intense but everyday workouts force new Japanese players to question whether they are getting enough work in or whether they will be ready when preseason games start a week after the start of camp instead of having a month before they start.

Kikuchi has become a strike-thrower and is more confident and mature than the pitcher who started a game after feeling a tinge from an old shoulder injury and didn’t tell anyone until it began to hurt during the game.


His first pro season was limited to two minor league games due to pain in his left shoulder. He was sent back to the farm after 11 days when he couldn’t crack the starting rotation. He was brought up for spot starts throughout the 2011 season, spending the last 1-1/2 months on the first team.

2012 was a big step forward despite not making his first start until July 1. He started all 17 of his games, going 9-4 with three shutouts over 108 innings, but shoulder inflammation caused him to miss two weeks from July 13 only to be deactivated seven days later when the problem was diagnosed. He finished the season on the farm, pitching as part of his rehab. His 2013 season was a similar story, going back to the farm to deal with shoulder discomfort on Aug. 8 and finishing the season in the minors pitching in rehab games.

Kikuchi didn’t start the 2015 season with the first team after suffering left elbow inflammation in camp as he was trying to iron out his mechanics.

On June 23, 2016, Kikuchi felt pain when he threw hard in his right oblique muscles. He returned on Aug. 5 and finished the year with the first team for just the second time in five seasons and with the exception of some shoulder fatigue, this spring has been fairly fit.

Activation / deactivation history

Figures in green represent Opening Day.

Activated Deactivated Reason
  3/18/2010 Shoulder pain
9/23/2010 End of 2010 season  
4/10/2011 4/21/2011  
6/12/2011 6/13/2011  
6/30/2011 7/1/2011  
8/11/2011 8/19/2011  
8/31/2011 10/19/2011 Postseason
10/29/2011 End of 2011 season  
  3/28/2012 Poor form
7/1/2012 7/27/2012 All-Star break
8/8/2012  End of 2012 season  
3/27/2013 7/13/2013  
7/30/2013 8/7/2013 Shoulder inflammation
3/26/2014 7/24/2014  
8/6/2014  End of 2014 season  
  3/25/2015 Elbow discomfort
4/28/2015  End of 2015 season  
3/23/2016 6/23/2016 Right oblique muscle
8/5/2016  End of 2016 season  
3/29/2017 7/8/2017 All-Star break
7/21/2017 10/4/2017 Postseason
10/14/2017  End of 2017 season  
3/29/2018 5/6/2018 Shoulder stiffness
6/1/2018 7/9/2018 All-Star break
7/29/2018 10/3/2018 Postseason
10/17/2018  End of 2018 season  

Notes: NPB teams often deactivate starting pitchers around the all-star break and prior to the postseason, since there are no limits on roster moves other than the 10-day period it takes to reactivate a player.

A tale of 2 catchers…

… or how many times can you beat a dead horse?

… with new notes about Tomoya Mori’s defense at the end.

I wrote recently about the Seibu Lions’ catching situation. The Lions this year became the first team to win a pennant and finish last in their league in ERA since the 2001 Kintetsu Buffaloes.

Having added the 2017 data for opponents’ offense against each catcher in NPB. This year, Ginjiro Sumitani was shoved aside as Seibu’s No. 1 catcher so that Tomoya Mori could hit more, and the Lions ERA soared from 3.53 (third best in the Pacific League) to 4.24.

I have heard that catchers’ ERAs — like batting average on balls in play against a pitcher — are not very predictive. I’m not going to replicate Sean Smith’s research here for NPB just yet, and I may be freaking out too much with small sample sizes BUT, when I saw the batting averages, on-base percentages and slugging averages against the three principle Lions catchers over two years, I was taken back.

First, the numbers for 2017:

2017 offensive results against the top three Seibu catchers.

Now the numbers for 2018, when Sumitani became No. 2 and Mori spent less time as a designated hitter and more time throwing out would-be base stealers:

2018 offensive results against each Lions catcher.

In 2018, Sumitani caught roughly half as much facing 1,433 batters instead of 3,233, but other than that and a poorer performance against base runners, his two seasons were carbon copies.

  • Batting average against: .247 (2017), .241 (2018)
  • On-base percentage: .308 (2017), .309 (2018)
  • Slugging average: .373 (2017), .374 (2018)

You can find the data for opposing hitters’ offense against NPB catchers in 2017 and 2018 here in roman characters and Japanese: 2017 romaji, 2018 romaji, 2017 日本語, 2018 日本語

I know this isn’t evidence that the Lions’ inflated their team ERA by making Tomoya Mori their No. 1 catcher, but it’s not a good look.

Something I was going to mention that on this week’s podcast but didn’t get around to it was whether Mori did more poorly in different counts than Sumitani or Masatoshi Okada. And it appears that he did in 2018. When the count was even, batters did quite a bit worse against Mori as they did against Okada and Sumitani. (.680 OPS vs .725 for Okada and Sumitani combined). But when behind or ahead in counts, Mori was worse.

I had speculated that Mori might be too predictable with runners on first since he improved a lot at throwing out base stealers this season, but there is  no hint of that in the data.

The bad news for the Lions is that Sumitani, who started all of Seibu’s postseason games behind the plate, has filed for free agency. In addition to lefty Yusei Kikuchi, who is being posted, and whose games Sumitani caught, the Lions could also lose slugging second baseman Hideto Asamura–who has also filed for free agency. If there is any good news there, it is that Okada, who began his career like Mori as a hitter who could catch, appears to be developing into a good game-caller.

Notes: After being criticized on Twitter for stating the fact that opposing batters hit better when Mori caught than when Sumitani or Okada did with the same pitchers, I mentioned my perception that Mori is not as good at blocking pitches. One of my followers disagreed, so I looked.

Mori was charged with a lot of passed balls BUT had fewer wild pitches charged to his pitchers, so the net effect was that he let relatively few runners advance on pitches that got past him. Is Mori weak at blocking balls? I don’t know, but the raw data I’ve seen doesn’t support that.