Johnson's homer to lead off the 10th inning propelled the D-backs past the Rockies, 12-11, on Wednesday afternoon at Coors Field.
"What a game," D-backs manager A.J. Hinch said. "I was pretty happy at some times, I was pretty upset at some times. I had every emotion I could imagine throughout that game."
The blast off Franklin Morales, which snapped an 0-for-9 streak for Johnson, saved the D-backs from what would have been a devastating loss.
"You've got to expect a fastball at some point," Johnson said. "He threw me two breaking balls. For whatever reason I had a pretty good hunch about a fastball and I looked for it in the right spot and it was there."
Said Morales, "I was trying to go inside and I caught a little bit of the middle. He got me."
It didn't seem like this was going to be a nail-biter when the D-backs scored six runs, three of which came on a home run by Chris Young, before the 23,773 in attendance had a chance to settle into their seats.
The Rockies managed a run in the second inning and put the first three men on in the third before Arizona starter Kris Benson was forced to leave the game due to soreness in his right shoulder. Reliever Leo Rosales was summoned and the Rockies wound up scoring six runs in the inning to take a 7-6 lead.
And the Rockies were not done.
Colorado added four more in the fourth and suddenly a game that seemed like it would be a cakewalk for the D-backs saw them trailing, 11-6.
"There was a time in the game that I even thought, 'I don't know if we can come back this time,'" Young said. "But the guys stayed with it. We didn't give up."
They sure didn't.
The bullpen stabilized as Esmerling Vasquez, Aaron Heilman, Bob Howry and Juan Gutierrez combined to toss 6 2/3 scoreless innings. In fact, over the final six innings, the Rockies managed just one baserunner when Carlos Gonzalez singled in the eighth.
"That was pretty much the story of the game," Young said of the relievers. "After the bullpen started doing that, it was all up to us to put some runs on the board."
That they did.
Young was in the middle of it again with a two-run single that keyed a three-run fifth and pulled Arizona to within 11-9. Then in the eighth, the D-backs rallied for two more runs, the final of which came on Tony Abreu's line-drive single to left.
It looked like the D-backs might take the lead in the ninth when they had the bases loaded with one out, but a close play at the plate and a flyout ended the frame and set the stage for Johnson's heroics.
"That's a big win for us," Hinch said.
And there's no question that had they not won, it would have been a devastating loss.
Steve Gilbert is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.