With Chris Tillman increasingly doubtful to be ready in the early part of the season, manager Buck Showalter has mentioned Lee, a 24-year-old left-hander, as a possibility to replace him.
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"He started to grasp a little bit the breaking balls, too, to really put him on another level," Showalter said. "Stuff-wise, he can pitch here. Just trying to get a feel if we can trust the other stuff. He's a confident young man."
Lee came out of the bullpen in his three other appearances this spring, and in 11 innings, has allowed two runs on seven hits, striking out nine and walking three.
In May 2016, Lee suffered a lat injury while pitching for Double-A Bowie and missed the rest of the season.
For Lee, starting instead of pitching in relief was memorable.
"It was definitely an amazing feeling. Definitely a little different from waiting so long because of the injury last year and coming back from it. Being out of the bullpen the first couple of games, starting just felt right. I felt like I was just getting back into it. Overall, the first start was pretty good, put up some zeros, and was happy with the results," Lee said.
"There [were] a little nerves, but it was good nerves. I have a little butterflies once in a while. Last night it was hard for me to sleep because I knew I had my first start in a little while. I was pretty pumped up and ready to get out there."
Rich Dubroff is a contributor for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.