When I think of aces I think in terms of FIP and stuff...
Basically, a guy who doesn't issue lots of walks, who can get hitters to swing and miss, and who keeps the ball on the ground or in the ballpark. Someone who can be counted on to eat at least seven innings most every time out and also to complete a game if necessary. And if the batter makes contact, it's weak contact for the most part.
I'd probably put Roy Halladay on that list for sure. Cliff Lee right behind him. Justin Verlander. Maybe Matt Cain. Jered Weaver and David Price. Strasburg and Kershaw are in their "up and coming" phase. I think that's about all I would count as "ace" right now, everyone else is at least a step behind.
I think there is a starting point with all aces that has it's roots in the scouting realm. This is not to throw out the stats, it's a key component of what makes an ace, but let's build a frame of what we think an ace looks like.
Some of us are familiar with the 20-80 scouting scale. It's important to get acquainted with it before we continue.
20-25 Not MLB quality
30-35 Well Below Average
40-45 Fringey tool
50-55 Average
60-65 Above average
70-75 Great
80 Elite
20's and 80's are rarely given out. 80's are really rare, it's the upper crust. For reference, Campana has legit 80 speed, Castro has 55 speed, and Harper has 60 speed. 60 is really good. It's just a notch below star level tool.
So keeping that scale in mind, what makes an ace? It starts with scouting pedigree. Aces rarely surprise, they never really pull a Jeff Samardzija. They are almost always highly touted prospects. Kevin Goldstein of Baseball Prospectus said the biggest ace surprise was Cliff Lee, who projected as a 3 (which is still awesome) coming through the Indians system.
Ace's have a mess load of 70's and have great command. You can't have anything below 50 as an ace, and really most aces have maybe one 50. Maybe.
I think the consensus ace of this era is Justin Verlander. Let's take a look at his repertoire.
Fastball 80
2-seam 60
Curveball 70
Slider 65
Changeup 80
Command/Control 70/70
Makeup 75
Justin Verlander is a monster pitcher, probably the best in the league. That's what a scout sees with an Ace, especially when he's trying to project. Great command and an elite repertoire. It can't just be average, it has to be elite.
Sometimes you can get by without 80's and still be an Ace. CC is like that, he probably maxes out at a 70 with his FB/SLDR combo, but he has GREAT control/command and that man can handle an extreme workload. Cliff Lee also probably has just two 70 offerings, but he has ELITE command and he takes a solid workload.
Kershaw has the repertoire, but for now he's just entering the "prove it" phase of Acedom.
This is where the stats come in. Brandon Morrow has Ace stuff, but until this point he has yet to harness it and "prove it." Kershaw is proving to be more than a thrower, he learned how to pitch and he's pretty deep into the "prove it" stage. Proving it is about going out there and really showing that you have it. We're talking 220 ip+ of Ace ball. What that means on the statistical spread has a lot of different definitions.
You can be Clemens, or you can be Maddux. You can go about it like Seaver, or you can go about it like Robin Roberts. But you have to be elite. You have to be the guy that is always talked about in the Cy Young voting, you have to be the guy that has a 75% QS and above stat AND have the other stats that lead the league, especially the advanced metrics.
In other words, every time you take the mound, your team has a great chance at winning the game. It's more than about the scouting grades, it's about more than the simple stats, it's about more than the extended stats. It's about all of it.
An Ace is a complete package, and you know it when you see it in the stats and in the stuff. It's the perfect melding of both worlds. That's why there's only about 5-10 of them now, depending on how stringent you are with the label.
Really that's what it is too, a label. It's not a moving target, it has the same meaning now than it did in 1960. It's a concrete label that has a concrete meaning. There aren't 30 aces in MLB.
My personal list? I'm sure I'll forget a few too.
Verlander
CC
Lee
Halladay
Weaver
Felix
Proving it:
Cain
Kershaw
Gallardo
Price
Great 2's
Garza
Shields
Greinke
Romero
Haren
Kennedy
Wilson
Like I said, I'm sure I'm missing a few names here. We should add to it.
) that every pitcher, no matter their pedigree or skill level, will have a bad day. Aces tend to have less bad days than everyone else.
