The Cardinals Should Utilize a Six-Man Rotation

Jack Flaherty has been too good to languish at Triple-A.
(Photo: Charles Edward Miller)

Before the season began, I noted some possible concerns regarding the Cardinals rotation — namely, that the team might have better, more talented starting pitchers in Triple-A than those on their major-league roster. At the time, the issue was only a potential problem: the season had yet to start. The potential became a reality even sooner than I expected, however.

A brief timeline:

  • On March 28, the Cardinals place Adam Wainwright on the 10-Day DL retroactive to March 26. Wainwright had injured his hamstring running sprints.
  • On April 3, Jack Flaherty, taking Wainwright’s place in the rotation, pitches five innings, giving up one run while recording nine strikeouts and just one walk.
  • On April 5, the Cardinals rush back Wainwright for the Cardinals’ home opener even though the latter hasn’t pitched in a competitive game since March 14, when he went five innings. Wainwright struggles in his debut, recording more walks than strikeouts, failing to finish the fourth inning, and losing more than 5 mph on his fastball during the game.
  • On April 11, Jack Flaherty strikes out 11 batters with no walks in seven innings, giving up just one run.

Wainwright alleviated some fears in his second start, pitching seven innings and maintaining decent velocity throughout his appearance. That’s a positive development, but that doesn’t really address the entirety of the problem. Jack Flaherty is sitting down in Triple-A right now despite having a possessing a better projection than Miles Mikolas, Michael Wacha, or Wainwright himself. It seems wasteful to let Flaherty keep pitching in the minors; at the same time, none of the Cardinals’ five starters is an obvious candidate for demotion. It’s an issue in need of a creative solution — namely, a six-man rotation.

On The Bernie Miklasz Show last week, Miklasz and co-host Michelle Smallmon discussed this very topic. (Go to 34:45 of the 7 am hour to listen to their conversation.) Smallmon noted Flaherty’s success, as well as Mike Matheny’s penchant for demanding eight relievers despite never having much use for the eighth reliever. The pair discussed the Cardinals’ bullpen depth which would help with a six-man rotation and Miklasz stated that, “Every pitcher has some sort of vulnerability or reason to be careful with their innings.” He then went down the list of Cardinals starters providing reasons why a six-man rotation might be beneficial.

  • Adam Wainwright: “Old… question of whether he can maintain his velocity over a full season.”
  • Luke Weaver: “Good pitcher, but I know they don’t want him throwing 200 innings this year.”
  • Michael Wacha: “Runs out of gas every year.”
  • Miles Mikolas: “In Japan, shorter season.”
  • Carlos Martinez: “He pitched 205 innings. He can do it, but again, do you really want to keep pushing him too hard?”
  • Jack Flaherty: “Twenty-two years old. They aren’t going to want to ride him too hard. They definitely want to limit his innings.”
  • Alex Reyes: “The plan is to have him be in the rotation, maybe not right away, but you know they are going to limit his innings.”

Smallmon pushed back on Carlos Martinez, making the argument that losing Carlos Martinez starts wouldn’t be a positive and Miklasz noted that, when the Cardinals had considered a six-man rotation three years earlier, the players strongly objected. Before getting to potential player objections, let’s first evaluate Miklasz’s — and presumably the Cardinals’ — logic for wanting to add an extra pitcher to the rotation.

We can start with Wainwright, who is — in baseball years, at least — relatively old. The 36-year-old pitched poorly and faded badly due to injuries last season. As noted, his velocity was poor in his first start of the season but better in the second. The difference between those two? The latter followed five days rest as opposed to the normal four. His start tonight will also be on extra rest. 

While in Japan, Miles Mikolas started 62 games over three years. Last year, Mikolas made 27 starts during a 26-week season, getting roughly six days off between appearances. In 2016, Luke Weaver made 21 starts and pitched 119.1 innings between the majors and minors. In 2017, he made 25 starts and pitched 138 innings between between Triple-A Memphis and the big club. He’s going to blow past that right after the All-Star Break at his current pace. Jack Flaherty made 23 starts and pitched 134 innings in High-A during the 2016 season and upped that to 30 starts and 170 innings last year between Double-A, Triple-A, and the majors. The Cardinals might not want to push too much beyond that this season. Alex Reyes is coming back from Tommy John surgery, so limiting innings and providing more rest seems self-explanatory.

As for Wacha, here’s how he has pitched the last three seasons through July compared to August and September:

Michael Wacha’s Annual Fade, 2015-17
Months K% BB% ERA FIP
April-July 21.1% 7.2% 3.79 3.54
August-September 18.8% 9.5% 5.19 4.70

Wacha did pitch well last September, but it was also after a poor August. To top it off, his velocity has been down so far this season, which raises concerns about his health.

With Carlos Martinez, I tend to side with Smallmon’s argument against giving him extra rest. As Miklasz noted, he pitched 205 innings last year. Since the beginning of the 2016 season, Carlos Martinez’s 426 innings is sixth in MLB behind only Chris Sale, Justin Verlander, Max Scherzer, Rick Porcello, and Corey Kluber. His 7.1 WAR during that interval is 17th in baseball and his 9.9 RA9-WAR (which uses run allowed and not FIP as the main input) is eighth. He’s just not a guy for whom the Cardinals should be limiting starts.

I went through the St. Louis schedule and kept the Cardinals’ five pitchers on a normal schedule to see how many starts they were scheduled to receive before the All-Star Break under the present schedule. I also noted the number of days off between starts the pitchers were set to receive.

Cardinals Starter Rest in Five-Man Rotation
Starts Days of Rest Between Starts
Wacha 16 5, 5, 5, 6, 4, 5, 4, 5, 4, 5, 4, 4, 5, 4, 6
Weaver 16 6, 5, 5, 5, 5, 5, 4, 5, 4, 5, 4, 4, 5, 4, 6
Mikolas 15 5, 6, 5, 5, 4, 5, 4, 5, 4, 5, 4, 5, 4, 5
Martinez 15 5, 6, 5, 5, 4, 5, 4, 5, 4, 5, 4, 5, 4, 5
Wainwright 16 6, 4, 6, 5, 5, 4, 5, 4, 5, 5, 4, 4, 5, 4, 6
Through the All-Star Break.

When we hear about objections to a six-man rotation, it is often related to a pitcher’s routine and normal schedule. That was Cole Hamels’ main point of contention this spring:

“I know that’s the new analytical side of trying to reinvent the wheel, but I was brought up in the minor leagues on the five-man [rotation], and that’s what I’m designed and conditioned for.”

What is striking about the table above is that there really is no typical routine. In two-thirds of the starts above, pitchers are pitching on five or six days rest, with only one third of the starts on the supposedly normal every fifth day. Due to the rainout on Monday, the next time Michael Wacha will pitch, he will be on seven days rest because the team preferred to have the emerging Luke Weaver pitch against the Cubs rather than the struggling Wacha.

To modify the schedule, I left Martinez’s starts as is and inserted Flaherty into the rotation just ahead of the first start currently scheduled to be on four days’ rest (in this case, Adam Wainwright’s on April 29). Here’s how many starts each pitcher would get as well as the number of rest days in between starts through the All-Star Break.

Cardinals Starter Rest in Six-Man Rotation
Starts Days of Rest Between Starts
Wacha 13 5, 7, 7, 6, 6, 5, 7, 6, 5, 6, 6, 7
Weaver 13 6, 6, 7, 7, 6, 5, 6, 7, 5, 5, 6, 8
Mikolas 13 5, 8, 6, 6, 6, 6, 6, 6, 5, 7, 5, 7
Martinez 15 5, 6, 5, 5, 4, 5, 4, 5, 4, 5, 4, 5, 4, 5
Wainwright 13 6, 6, 6, 7, 6, 6, 6, 5, 7, 5, 6, 6
Flaherty 11 7, 7, 5, 7, 6, 5, 6, 6, 6, 5
Through the All-Star Break.

Just as with the current, more traditional arrangement, two-thirds of the starts here would be made on five or six days of rest. The starts with four days rest before — just five or six per starter before the break — are now replaced by seven-day periods. The non-Martinez starters miss just two or three starts apiece and Jack Flaherty gets to prove he belongs in the majors. We don’t know that this approach would lead to better health or performance, but given the makeup of the Cardinals rotation and the desire to limit innings, this setup makes a lot of sense. If a starter gets injured before June, the typical five-man rotation will make more sense. Once the end of May arrives, the Cardinals will have another candidate for the rotation in Alex Reyes.

The scheduling for this rotation is a little difficult to pull off due to the desire to keep Martinez on somewhat normal rest, but it is certainly not impossible. St. Louis doesn’t actually need an eighth pitcher in the bullpen, and never actually use one when they have an extra guy. They might as well do everything they can to maximize the talent they have available to them in Memphis and St. Louis. That means getting Jack Flaherty back to the majors and getting creative with a rotation that can make the most of a sixth man.

We hoped you liked reading The Cardinals Should Utilize a Six-Man Rotation by Craig Edwards!

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Craig Edwards can be found on twitter @craigjedwards.

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tehzachatak
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tehzachatak

in with the first “just another Craig Edwards Cardinals puff piece”

Ryan DC
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Ryan DC

beat me to it

The Guru
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The Guru

can say same for travis and pirates