JUPITER, Fla. -- Standing on the bullpen mound, with manager Mike Matheny and closer Trevor Rosenthal observing, Kevin Siegrist threw an extended side session on Tuesday, one day ahead of the team's report date for pitchers and catchers. What Matheny and Rosenthal saw was not only a pitcher whose arm seems to have bounced back well after career-high usage in 2015, but also one showcasing a new pitch.
Siegrist will spend the next seven weeks fine-tuning a curveball that will replace the slider as his breaking pitch. He has taken Tyler Lyons' grip and Adam Wainwright's how-to in order to develop a feel for a pitch he hadn't been able to previously master.
"Waino told me to really focus on the shape of the pitch," Siegrist noted. "That actually really helped me. Maybe that's why I never had a really good breaking pitch, because I never could understand the thought process of how you throw one. This year, with the grip I have, I don't really have to think about manipulating the ball. I can just throw it."
Siegrist, 26, hadn't intended to wait so long to develop the breaking pitch, but he had too much to prove last offseason with his health that his repertoire took a temporary back seat. Things were different this offseason, one in which Siegrist refrained from throwing off the mound until February.
Tuesday's bullpen session, he said, was his fourth leading up to Spring Training.

"Terrific," Matheny said of watching Siegrist toy with the curve. "The changeup still looks good, but the curveball is a wipe-out, strikeout pitch. It's just adding to the complexity of the approach for the at-bat."
Siegrist mostly phased out the slider last year, throwing it seven percent of the time, according to fangraphs.com. On the contrary, his percentage of changeups thrown jumped from five in 2014 to 18 in 2015. He expects to rely on that pitch heavily again this year.
As for the curveball, Siegrist said he will soon seek feedback from hitters who can stand in and track it. Thus far, the only person to watch the pitch from the batter's box has been Wainwright, whose mastery of the curve makes him an ideal evaluator.
"Obviously, to learn a new pitch can be frustrating a little bit, but I like the shape of it right now," Siegrist said. "Now, it's learning how to use it against hitters. It feels really good in the bullpen."
Siegrist said he is also encouraged by how good his arm feels at this point in the build-up process. He is in unchartered territory, having made a league-high 81 appearances covering 74 2/3 innings last year. The Cardinals have fortified their bullpen this winter so as to prevent such heavy workload again.