On the 15-day disabled list with a lingering strain in his lower back, Robertson spent much of the weekend in pain. That was until Tuesday morning, when Robertson said he woke up feeling remarkably better.
He threw long tosses from center field on Tuesday afternoon and even threw a few balls from the mound, and said he is on schedule to make his expected return to the bullpen on Thursday.
"I don't see anything keeping me from that," Robertson said of his scheduled return.
Tuesday's workout served as a stark turnaround for Robertson. He spent Saturday out with back spasms, and said he was also restricted in what he could do on Sunday. This was after six days of no improvement since he was placed on the disabled list on May 14 (the move was backdated to Robertson's last action on May 6).
"I'm just relieved, because I've never had an issue down there, and for the first six days of it I was pretty concerned," Robertson said. "I didn't feel like it was getting better."
The training staff switched his anti-inflammatory medicine over the weekend, which kick-started his recovery. Robertson said the big test will be if he feels as good on Wednesday, the day before his return, as he did on Tuesday.
Robertson made the switch from the starting rotation to the bullpen, where he is 1-0 with a 6.30 ERA in 10 innings pitched, at the start of this year. He said coming out of the bullpen should help him ease back into things. Nonetheless, he's leaving the disabled list more cognizant about how to take care of his back.
"I'm going to be a lot more aware and cautious with anything to do with my lower back," Robertson said.
Kyle Austin is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.