A new approach for Strasburg?

Stephen Strasburg will make his first rehab start on Sunday, less than a year after undergoing Tommy John surgery.

A Buster Olney ESPN Insider piece from Friday morning reports that Strasburg is willing to make changes, including some adjustments to his rehab that focus on upper-body strength. Olney also said that Strasburg will change his pitch mix:

During Strasburg’s brief window of professional baseball last summer, about 95 percent of the fastballs he threw were four-seamers—fastballs in the range of 97-100 mph, hard but with comparatively little movement.

At-bats against Strasburg tended to be longer—3.91 pitches per plate appearance. In the aftermath of his reconstructive elbow surgery, Strasburg has focused on throwing a two-seam fastball—a pitch with a lot more lateral movement.

Last summer, Strasburg threw 469 four-seamers and 153 two-seamers, which is more like 75 percent four-seamers as opposed to Olney’s number of 95 percent. Still, that’s a lot for a pitch that’s very flyball prone—Strasburg’s four-seamer generated a groundball less than 35 percent of the time it was put in play. The two-seamer had a rate of 47 percent, which is below average compared to the league average two-seamer, but is a better batted-ball option than the four-seamer.

Strasburg’s changeup and curveball were lethal last year (54 percent and 34 percent whiffs per swing, respectively), so going to the two-seamer early and the change/curve combo late could be nasty. As if Strasburg wasn’t nasty already.