Actually, this was his backup plan and on paper, was pretty clever.
Davies gets hurt so you put a reliever in, allowing Mazzaro some time to get loose. As a starter, Mazzaro needs extra time to warm up, unlike your normal relievers. Then Mazzaro takes you 5 or so innings, into the regular end-of -the-game bullpen.
Since Mazzaro was supposed to start the next day, you DL Davies and bring up a guy to start or demote a reliever.
So he had a backup plan for Davies which was actually pretty clever.
What he did not plan for was the shellacking. But what manager does? After his second inning of work, my guess is Yost asked the kid "can you give me one more, we need to save the bullpen" and he obviously wanted to redeem himself and went out there.
As an aside, I had Mazzaro active in a high stakes AL only league for his 2-starts. I saw the line and spend the next 30 minutes going to EVERY web site there was, hoping to find out it was a mistake.
Sorry RT
And FWIW, I have Wakefield on the bench in this league, who now gets 2 starts so I can pretty much guarantee Wake will kick some ass this week - from my bench

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