"I felt good today," De La Rosa said. "I was being aggressive with hitters and threw a lot of strikes. I was trying to paint the zone as much as I could."
The lone run that De La Rosa allowed came in the fifth when, with one out and the bases loaded, Michael Bourn hit a grounder to the hole at short that Nick Ahmed was unable to field cleanly.
"I don't even know if I would have had a play at home," Ahmed said. "It may have been bang-bang with a perfect throw. I may have tried to go to first. I was rushing, obviously, to try and make a good play and kind of clanked it, but unfortunately that's how it goes sometimes."
De La Rosa was able to retire the next two hitters to end the threat with no further damage.
"I thought he did a great job navigating that," D-backs manager Chip Hale said. "Did a nice job to get out of that with just one run."
The D-backs have emphasized all season the importance of De La Rosa keeping his focus on the mound. He showed how far he's come in that regard in the fifth when he bounced back after he was clearly not pleased with a 2-1 pitch to Miller in the fifth that was called a ball.
"I tried to lock in and try to get a double-play ground ball," De La Rosa said of the rest of the inning. "I did, but then I had to do it again and get the next two hitters. I think it was important to have the ability that inning to lock in and stick with the game plan and get out of that inning without too much damage."
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.