CLEARWATER, Fla. -- Phillies right-hander Zach Eflin entered camp last spring at 198 pounds, nearly 40 pounds lighter than the spring of 2016.
Eflin arrived in camp this spring at 220 pounds, gaining nearly 22 pounds of muscle, almost exclusively in his legs. He is confident stronger legs will lead to improved performance on the mound, and perhaps lead to a job in the Phillies' rotation.
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"Now that I have some legs back, they're not fully there, but once they're fully there, it will be amazing," Eflin said after allowing one run over 1 2/3 innings Saturday in the Phillies' 9-6 victory over the Orioles in a Grapefruit League game at Spectrum Field. "I'm just really excited. I'm putting a lot more pressure on my legs and I'm using my legs to where I don't even feel my arm when I throw. I don't think I've ever felt like that in my life."
Eflin, 23, had a pair of surgeries to repair the patellar tendons in his left and right knees following the 2016 season. He said he pitched on a pair of "sticks" last year, which might explain why he went 1-5 with a 6.16 ERA in 11 starts.
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"I think one of the things that's happened for [Eflin] in the past, is you've seen a wide range of velocities so one of the things that we talked to him about was having a lot of conviction and boldness on his pitches," Phillies manager Gabe Kapler said. "When he delivers the baseball to do it with boldness. He did that today. He came out and let every pitch [fly]."
More powerful legs can translate into improved velocity. Eflin showed some life on his fastball Saturday, striking out Cedric Mullins on a 95-mph heater in the first inning. His fastball averaged 93.6 mph last season.
"I tell you what, it feels better throwing my fastball right now," Eflin said. "Last year and the year before I kind of compensated for things I had to do to get the ball to the glove. This year I'm just going out and pitching. I'm really excited about that, being able to go out pain-free and healthy and focus on pitching alone."
Eflin is one of a handful of pitchers in camp competing for a job in the rotation. Aaron Nola is a lock for a role, and Jerad Eickhoff, Vince Velasquez and Nick Pivetta are heavy favorites. It leaves Eflin, Ben Lively, Jake Thompson, Mark Leiter and Tom Eshelman competing for the final job.
Unless, of course, the Phillies sign Jacob Arrieta or another veteran starter.
"I don't really care about any of that stuff," Eflin said about the front office's pursuit of starting pitching. "If they do it, they do it. If they don't, they don't."
The Phillies host the Yankees in a Grapefruit League contest Sunday afternoon at Spectrum Field, live on MLB.TV at 1:05 p.m. ET. Nola, who is expected to start for the Phillies Opening Day, is scheduled to begin the game.