Of all of the potential free agents the Mariners have, Hisashi Iwakuma is by far the most interesting. He was brought in on a contract that initially was valued at just 1.5 million dollars (with a total 3.4 million dollars in incentives), and despite not even making the rotation out of spring (thanks to diminished velocity, sitting mainly 88-89 MPH in spring training), he has clearly been worth that. There is almost no doubt that he will get more money than that this off-season, and at age 31, he will get more than a 1 year deal. So what should be the Mariners’ approach when it comes to Iwakuma?
According to ERA -, Hisashi Iwakuma has been above average with a 87 (remember that 100 is league average), but FIP – has him at 117. His FIP comparable is Tommy Hanson, while his ERA comparables are Greinke, Latos, Diamond, and Parker. A .279 BABIP and strand rate of over 80% have significantly helped his numbers. With men on base, Iwakuma gives up an OPS of just .600 and when runners are in scoring position, the OPS shrinks to .543. For the year, he is giving up a .730 OPS. So why the difference? Is it fluky, i.e. something we would expect to regress, or is it a skill that Iwakuma actually possesses. Many people believe that big time pitchers have the ability to “limit damage” or actually pitch better in pressure situations. DIPs theory states that this isn’t true, and that over large sample sizes, strand rates (or LOB %) will stabilize. Especially with the small sample size that we have this year (and lack of data to see if he is actually throwing harder with runners on base), I tend to believe DIPs theory here. As far as luck goes, Iwakuma has a .88962 xOPS off the bat, versus a league average xOPS of .93546 (league average has a .679 OPS in play, while Iwakuma is giving up a .639 OPS on balls in play, which could be a combination of luck/park/and the amount of grounders he gets). In total, Iwakuma is giving up an OPS of .730, with a total xOPS of .729. So it doesn’t appear that Iwakuma is being lucky (or unlucky, counteracting an argument that his HR/FB % should come down) as far as the total number of hits and homers he is giving up. Since league average OPS is .725, he looks very much like about an average pitcher here.
For the season (on non-bunts), Iwakuma’s average distance on batted balls is 259.399 feet (Hanson’s is 266.835, so while his K/BB/HR is the same as Hanson’s when adjusted for parks, he is giving up weaker contact on average).
As far as velocity goes, Iwakuma is a little below league average (90-91 MPH on average). He has an assortment of pitches and tries to pitch off his fastball by showing a splitter and a sinker off of it. Here is a breakdown of his pitches:
4-seam fastball: Pitcher Batted Ball Distance with and average distance of 257.555. Velocity: 86.5-94 MPH, 90.3 MPH on average.
Splitter: Pitcher Batted Ball Distance with and average distance of 270.619. Velocity: 82-91.4 MPH, 86.2 MPH on average.
This is his knock out pitch that he throws when he gets ahead, but it has also been the pitch that has been hit the hardest when left up. The splitter having a high distance makes some sense anecdotally. It seems that he has had a lot of problems controlling the pitch this year.
Sinker: Pitcher Batted Ball Distance with and average distance of 250.507. Velocity: 86.5-93.1 MPH, 90.1 MPH on average.
Slider: Pitcher Batted Ball Distance with and average distance of 255.814. Velocity: 74-88.9 MPH, 82.2 MPH on average
There is some classification issues between the slider and splitter in pitch F/X, and they look quite a bit similar when you watch him pitch. I have had some problems recognizing the difference.
Curveball: Pitcher Batted Ball Distance with and average distance of 246.294. Velocity: 67.5-77.5 MPH, 72.8 MPH on average.
Iwakuma throws the curve the least but gets the lowest distance on batted balls. He also seems to have some issues with control and consistency.
Perhaps the big story with Iwakuma this year has been how rarely he was used at the beginning of the season, and how terrible he was out of the bullpen. Then when he was used as a starter later in the season, he was excellent (at least according to ERA).
As a reliever: Pitcher Batted Ball Distance with and average distance of 265.224
As a starter: Pitcher Batted Ball Distance with and average distance of 255.2
So he has been a lot better as a starter (at 10 feet, it is about the difference between pre-Mariner Oliver Perez and Mariner Oliver Perez). For comparison, here are some notable pitcher’s average battled ball distance:
Tim Lincecum this year: Pitcher Batted Ball Distance with and average distance of 254.451
Hector Noesi this year: Pitcher Batted Ball Distance with and average distance of 262.647
Steve Delabar: Pitcher Batted Ball Distance with and average distance of 266.12
Yu Darvish: Pitcher Batted Ball Distance with and average distance of 248.925
So as a reliever, he was Delabar hittable (without the awesome K/BB), but as a starter, he has been around Tim Lincecum hittable (1.00 HR/9IP, 1.58 GB/FB, 24.7 LD %, .502 SLG allowed on the road). So while he is better than Hector Noesi (obviously), there is still some concern about him being hittable. You can live this way if you counteract it with a good K/BB. Since becoming a starter, Iwakuma’s K/BB is solid at 2.63 (league average is 2.47) but he has been hittable, with a 1.11 HR/9IP even with Safeco as the home park. He has been a much different pitcher on the road than he has been at home, as opponents are hitting .273/.343/.474 against him on the road. That is a pretty similar slash line to Mark Teixeira and Kendry Morales. As you would imagine, his home run rate is much higher on the road (a baffling 1.64 HR/9IP, which is the same as Phil Hughes’, who pitches in Yankee Stadium), but his strikeout rate is quite a bit lower on the road (15.9% to 21.5%). This, and the difference between Safeco and most other ballparks, may be why he is giving up so many homers on the road, he isn’t missing enough bats.
So if the Mariners do not re-sign Iwakuma, what are their other choices? In the organization, the Mariners have the “big three” in Danny Hultzen, James Paxton, and Taijuan Walker. Hultzen’s season ended in somewhat disastrous fashion as he couldn’t throw strikes in AAA. In AA, he was flat out dominant, looking completely ready for the big leagues. At this point, it is really hard to know what to expect from Hultzen. Perhaps he puts it back together in the spring or in the early going in Tacoma, and perhaps he is in need of a major mechanical overhaul that sets back his ETA to the Majors by significant time. Perhaps the rest of the off-season will allow him to come back stronger than ever, but perhaps not. He is certainly a rotation candidate, but by no means a rotation lock.
Walker is the youngest of the bunch, and has the highest ceiling. He is probably the least ready (depending on how you interpret Hultzen’s command issues), but he was solid (not spectacular) at a tender age in AA (A to AA is an extremely tough jump, and he handled it well). He may not actually be too far from the Majors, but it would be extremely unlikely to expect him to make the club in the spring. I would let him travel and play with the big league club, but wouldn’t allow him on the big league roster until he either dominates AA or proves serviceable in the PCL (skipping AAA altogether would not bother me at all if he pitched well in AA).
James Paxton at this point might be the best bet of the 3 to make the rotation next year. He had a great 2nd half after he got healthy and should start in Tacoma next year (unless he has a great spring and makes the big league club).
The rotation might look something like this next year without Iwakuma: King Felix, Erasmo, Vargas, Beavan, (assuming the club doesn’t bring back Millwood, which I will look at in a future post), plus one of the big 3. This is not a very deep rotation. If they do not re-sign Hisashi Iwakuma, I would expect them to bring in at least starter from the free agent market (and hopefully beyond just the minor league free agent market). This way they are not pressured to rush one of the big 3 if they are not ready. The rotation could use all of the help it can get, but price is everything. For the right price, you will bring in just about anyone. Iwakuma may give the team a “discount”, but I wouldn’t if i were him because of the way the Mariners handled him.
I would expect Iwakuma to struggle in hitter friendly environments, which sounds like an obvious thing to say, but I think his hittability makes him even more vulnerable. Safeco allows you to hide somewhat hittable pitchers as long as they don’t walk batters and miss some bats. Perhaps with the Mariners focus on defense, ground-ball pitchers are more valuable, as you would expect them to turn more balls into outs. Unlike the Tigers, with their terrible difference, the miss bats at all cost approach may not be as wise for the Mariners to take, as the defense and ballpark can hide some flaws. I think he is closer to average to below average (as his FIP states) than being an above average starter. If the Mariners bring him back, it should be more as a number 3 starter in the rotation and the salary that would entail. This would be around a 6-10 million dollar salary per year. On the wrong side of 30, a long term deal just isn’t going to happen, but a 3 year deal isn’t out of the question. That would come with it’s risks, but could really give the Mariners some rotation stability until we know more about how the “big 3” fit into the Major League rotation.