First, Maddux was convinced no hitter could tell the speed of a pitch with any meaningful accuracy. To demonstrate, he pointed at a road a quarter-mile away and said it was impossible to tell if a car was going 55, 65 or 75 mph unless there was another car nearby to offer a point of reference.
“You just can’t do it,” he said. Sometimes hitters can pick up differences in spin. They can identify pitches if there are different releases points or if a curveball starts with an upward hump as it leaves the pitcher’s hand. But if a pitcher can change speeds, every hitter is helpless, limited by human vision
“Except,” Maddux said, “for that [expletive] Tony Gwynn.”