In those days, up until the 90’s ballplayers extended their arms starting when they were young by playing out in the fields, parks, streets, farms etc. all day, EVERY DAY! Built strength gradually over time …today it’s, play a game that’s on the schedule…and throw really fast
"Lefty Grove was one of the fastest throwers who ever lived.
In actual speed, I would rank him ahead of Sandy Koufax.
But he did not show much of a curve.
Nor did he need to when he was young and strong."
'Schoolboy' Waite Hoyt.
"Bob Feller never saw the day when he could throw as fast as Lefty Grove.
Lefty was bigger, more powerful, and had a smoother delivery."
Mickey Cochrane, Grove's regular catcher.
"Leave me out of this Johnson-Feller thing.
I didn’t hit against Johnson when he had all his speed.
But I can tell you one thing:
Feller has never shown me a fast ball like Lefty Grove was throwing my way for ten years.
Against Grove you were up there swinging at an aspiring tablet."
Charlie Gehringer when asked to choose whether Bob Feller or Walter Johnson threw a better fastball.
"I missed Walter Johnson, but Grove was the fastest pitcher and best pitcher I’ve ever seen.
He had a great arm and a sullen disposition. Bill Dickey once told me nobody but nobody could throw a fastball past him if he knew it was coming:
And then Grove threw three past him on one time at bat."
Tommy Thomas.
At age forty, Lefty Grove pitched a thirteen-inning, complete game victory in Detroit.
In order to do that, he threw the baseball 214 times.
Lefty Grove won 300 games while losing just 141 for a .680 winning percentage that is easily the best of any 300-game winner. Grove captured a record NINE ERA titles AND led the America League in strikeouts for each of his first SEVEN seasons.
Remember too that Lefty Grove was held in indentured servitude by the Baltimore Orioles from 1920-24 where he had a 108-36 record, Lefty could have probably won about 380 games if he been allowed to go to the MLB in say 1921.
It took 100,600 dollars to get Lefty Grove to Philadelphia, a higher price than the $100,000 Yankees paid for Babe Ruth.