Quote Originally Posted by RocketDawg View Post
The ball can rise because of aerodynamic lift, but it can't accelerate after it leaves the pitcher's hand. The only acceleration at that point is due to gravity.
When a hitter swings under the ball and misses, baseball announcers sometimes say the pitcher got him with a "rising fastball." But technically, this pitch cannot exist if thrown overhand--it's impossible for a pitch thrown downward to buck gravity and achieve upward lift.