The superlative Lefty Grove stands as one of the most underrated pitchers of all-time. Sure, he's a Hall of Famer (class of '47), but you don't often hear his name mentioned as being on the short-short-short list of best pitchers in history. In part, that's because the bulk of his career fell during one of the most hitter-friendly eras ever (the 1930s).
Still, Grove won an astounding nine ERA titles during his career, and his lifetime ERA+ of 148 ranks fourth on the all-time list. When you think of the best of the best, Grove should come to mind.
Competitive? That was Grove. Ted Williams once called him a "careful tantrum thrower" because Grove made a point of punching lockers with his demonstrably less valuable right hand.
Grove made hay with a terrific fastball -- "the fastest ball in existence," according to former major-league catcher Cy Perkins, and an offering that helped him once strike out Babe Ruth, Lou Gehrig and Tony Lazzerri on a total of 10 pitches. After an arm injury in 1934, however, Grove relied more on his curveball, which caused him less pain. Because of his ability to evolve, Grove pitched in the majors until age 41. Of that evolution, Grove once said (source: SABR):
"I actually was too fast to curve the ball while with Baltimore and Philadelphia. The ball didn't have enough time to break because I threw what passed for a curve as fast as I threw my fastball. I couldn't get enough twist on it. … Now that I'm not so fast I can really break one off and my fastball looks faster than it is because it's faster than the other stuff I throw. A pitcher has time enough to get smarter after he loses his speed."
"Too fast to curve the ball"!
Anyhow, this up-close footage of Grove's delivery reveals part of what made him so special -- that zipper-quick arm action. Dig it:
It's impressive how quickly Grove's left elbow gets out in front of his ball hand as he strides toward the plate. That's a good start toward throwing "the fastest ball in existence."
And here's a GIF that takes another angle and shows Grove in understated warm-up mode ...
I'm no scout, but you see a couple of things here. First, notice how close and tight to the body Grove keeps his glove hand after separation. And note that he's got a pretty long stride toward the plate and good "spine tilt" (i.e., posture). Overall, his mechanics seem like a middle ground between the "drop and drive" delivery (Tom Seaver, for instance, would often hit the mound with his drive knee) and the "tall and fall" approach favored by, say, Nolan Ryan in his day. Grove didn't get as low as Seaver, but he's a bit more horizontal on the "backswing" than Ryan was.
The lesson? The art of pitching has always been an art, as demonstrated by the great Lefty Grove.