His is a spectacular pitch , albeit at the slower end of the spectrum .
Clayon Kershaw has arguably the most effective curveball in MLB and throws his at 73 - 77 off of an average fastball of 93mph .
Clayon Kershaw 's is a spectacular pitch , albeit at the slower end of the spectrum .
Clayon Kershaw has arguably the most effective curveball in MLB and throws his at 73 - 77 off of an average fastball of 93mph .