"He had a stretch there where he's pitched as well as anybody probably in the league for a while, and I think soon thereafter after Randy went down, maybe a little bit later, he went on a nice run that kind of bridged the gap," Arizona manager Bob Melvin said of Davis.
And now, Davis has a chance to do even more good, as he'll get the ball on Thursday for Game 2 of the National League Division Series against the Cubs, with the Diamondbacks holding a 1-0 lead in the best-of-five series following a 3-1 victory on Wednesday.
At 32, Davis -- with his fourth team in his nine-year career -- has experienced something of a career revival with the Diamondbacks this season.
Davis posted the most victories in his Major League career while also helping pick up the pieces following the loss of Johnson, who had season-ending back surgery in July. Davis continually came up big in the second half, posting an 8-2 record with a 4.24 ERA.
Overall, Davis went 13-12 with a 4.25 ERA in 33 starts, marking the fourth consecutive season he's pitched 190 or more innings.
He also experienced something unusual this season, something that he hadn't experienced in any other Major League career -- a September to remember.
Before now, Davis had never appeared in the postseason and only once -- in 2003, when he spent part of the season with Toronto -- did he spend any time on a team that finished with a winning record.
"This is actually the first time I've been over .500 on a team, too," Davis said. "I found out the year went by a lot faster, definitely. September came around a lot quicker than I had anticipated, and it feels good that we're actually going into October. I'm real excited, and hopefully I can help my team advance into the next round."
This, at least statistically, made him an easy pick to start the second game of the best-of-five series against the Cubs, a team that he has defeated more than any other team in his career. Overall, Davis is 7-5 with a 3.39 ERA against the Cubs in 13 starts.
That Davis on Aug. 25 defeated the Cubs -- a team that's just 19-24 this season against left-handers -- certainly didn't hurt Davis case, either. But why has he been successful against the Cubs?
"It just seems that every time I face them, it feels like I can execute a plan that I've been working on for the week before that," Davis said. "It's something that I study and figure out what hitters' weaknesses are, and I try to execute my pitches and let my fielders work behind me."
If only it were that easy all the time.
Like any other Major League pitcher, Davis makes adjustments during the regular season. This season was no different, as Davis had to slow down his delivery and focus on cutting down on his walks. It worked. He went 8-1 with two no-decisions in an 11-start stretch in the second half.
"I think the second half I just came and I was more efficient with my pitches, and I wasn't walking nearly as many people," Davis said. "It might have been something a little bit with my mechanics. [Pitching coach Bryan Price] and I, we worked on it constantly between each start, and if it wasn't one little thing, it was always another little thing that I always had to correct in my mechanics.
"It's just a small adjustment in my mechanics that I pick up, and I'm able to repeat it every time, instead of fighting myself out there on the mound and figuring out what the heck I'm doing wrong."
The Diamondbacks certainly don't have any complaints, as Davis has consistently pitched deep into games, giving the back end of Melvin's rotation a much-needed breather down the stretch.
"He's done exactly as advertised; He gives us innings, he gives us wins, he takes the ball out there, takes the pressure off the bullpen, and is a guy you can count on," Melvin said. "He's been very, very good for us."