"Another huge step for me, I guess," Burnett said with a wry smile. "My first official bullpen."
Burnett threw 30 fastballs off the rubber on Thursday morning, just like he did four days earlier, at an estimated 80- to 90-percent intensity. He let it go on his last two, and "my 30th pitch felt as good as the others." It felt, in Burnett's words, "phenomenal."
Burnett still has to work in his offspeed pitches -- which he's been throwing off flat ground -- and estimates he'll need two to three more bullpens before he can progress to a live BP session and then ultimately get in games.
That's a lot of steps to complete in 18 days, which is why Burnett seems likely to start the season on the disabled list. The important thing is he's clearing major hurdles seven months after August forearm surgery.
Simply throwing off a downhill plane is not something his arm was able to stand up to last season.
"The biggest step probably isn't physically; it's more emotionally and mentally," Burnett said. "Last year, I felt so good, and then every time I would get off the mound it would go downhill after a couple of pitches. So it's a big mental step for me, more than physically. Obviously, for the training staff, it's physical, but for the player, it's mental. Today was a big hurdle. I didn't fatigue, like I did [on Sunday]. Hopefully, it progresses, just like my throwing program."
Alden Gonzalez is a reporter for MLB.com. Read his columns and his blog, Gonzo and "The Show", and follow him on Twitter @Alden_Gonzalez. This story was not subject to the approval of Major League Baseball or its clubs.