Diaz, the Bucs' No. 8 prospect according to MLBPipeline.com, spent last September on the Pirates' roster, appearing in two games. But after recovering from surgery on his right elbow for most of the past four months, getting summoned to the big leagues was even more gratifying this time.
"The first time I got called up, it was a joyful moment -- but this time was a lot more special," Diaz said through translator Mike Gonzalez. "And what made it more special is because I had to overcome some really tough challenges -- recovering and recovering 100 percent and going through the injury that I went through, the mental effect, the physical effect, it's hard.
"That's not something that is easy for anyone, and for me to [not only] be able to say, 'Man, I made it up here,' but [to say], 'I had to fight through some challenges and I didn't become discouraged, I didn't give up, I didn't quit,' you know, that makes this opportunity a lot more special to me."
Diaz emerged from Spring Training on the 15-day disabled list and was transferred to the 60-day DL in May following arthroscopic surgery. What followed was physical rehabilitation, and then rehab stints with two teams before being activated and sent to Triple-A on Wednesday.
The timing for the injury was unfortunate in that both Pirates' catchers -- Francisco Cervelli and Chris Stewart -- spent time on the DL, meaning in lieu of being able to turn to Diaz, the Bucs instead claimed two catchers off waivers.
But the timing this week was much more serendipitous for Diaz and the Pirates. Fryer's wife, Allison, gave birth to twins (Abigail and Hayden) on Saturday morning. That meant Diaz was in the Majors three days after being cleared.
"It actually turned out to be fortuitous timing, because Diaz has been back and doing a nice job and playing," manager Clint Hurdle said. "He's been looking forward to playing all year. The season didn't start the way he wanted, but he didn't go anywhere other than 'OK, I need to rehab first, I need to rehab, and once I rehab, I need to play.'
"It wasn't, 'Poor me,' or 'Why did this happen?' He dealt with it professionally and has responded now professionally with his play."
With Cervelli still being monitored as he continues to ramp himself back up following surgery on his left hand, it is entirely possible Diaz will get his first Major League start in Sunday afternoon's series finale with the Phillies.
"Super grateful I was able to recover well, but during that process, I didn't feel frustration, because it was something I just had to deal with," Diaz said. "But ... I'm just glad to be here now; God knows the perfect timing."
Chris Adamski is a contributor to MLB.com and covered the Pirates on Saturday.