Pettitte had gone to instructional league after last season to work on the cut fastball.

"I toyed with it last spring," he said of the cut fastball.

The mechanics of the cut fastball are not elaborate or complex.

At some point, Rivera's cut fastball will stop being so invincible.

He mixed in some breaking pitches but no cut fastballs.

Rivera's recent struggles seemed to be related to the movement of his cut fastball.

"To face his cut fastball is the toughest assignment in baseball to me."

"On the cut fastball, I can still come from on top."

When he wanted to use his cut fastball, it deserted him.

Martinez said that he used his new cut fastball three times Friday, all in the third inning.