I have the Canon 70-300 IS f/4-5.6 and the Canon 70-200L (non IS).
You will lose a bit of sharpness at the long end of the 300...but I've always been happy with the lens.
The 300 does have variable aperture and is not as fast as the 200....so this may limit your ability to separate subject from background in sports shots.
Sent from my SM-N950F using Tapatalk