PHOENIX -- As he watched Rockies pitching coach Darryl Scott head to the mound, Corbin Carroll gathered his thoughts.

The D-backs’ rookie left-handed hitter knew that with two outs, runners on second and third in the bottom of the ninth with Colorado up by a run, he might get intentionally walked so that right-hander Pierce Johnson could face the right-handed-hitting Christian Walker.

Rockies manager Bud Black, in the dugout, looked at the numbers which told him that Walker has had a lot of success against his club over the last few seasons. Black also knew that, for whatever reason, Johnson has better career numbers against left-handed hitters than right-handed ones.

“I understand where they're coming from,” said Carroll, whose two-run single gave the D-backs a 5-4 walk-off win and a share of the National League West lead with a four-game sweep at Chase Field.

“I didn't have a hit in this game. You know, if they're willing to pitch me, I'm willing to hit.”

When it became clear he wasn’t going to get intentionally walked, Carroll’s mind began to focus on how he wanted to approach the at-bat.

“I think you don't try to play the hero,” Carroll said. “I think you stick with your process and just treat it like another at-bat.”

Carroll also knew that while the Rockies might not intentionally walk him, they might not throw him a strike in hopes of getting him to chase pitches out of the zone.

Johnson’s first pitch was a curveball that was below the strike zone, and Carroll swung through it.

“I was trying to not expand the zone,” Carroll said. “Didn't do a very good job of that.”

The next pitch was another curveball outside the zone, and this one Carroll took for a ball to even the count.

Johnson’s breaking ball had more horizontal action than Carroll had expected and a little more bite to it. So he adjusted his approach to be able to hit that pitch better.

“[It] left me a little bit more vulnerable to fastball out over [the plate],” Carroll said. “But I feel like I can handle a fastball out over [the plate] and elevated, and that would give me a better shot to get a swing off on a curveball in the zone.”

“Curveball is my strength,” Johnson said.

But Johnson was concerned that Carroll might be sitting curve on that third pitch, so he decided to throw a fastball outside thinking that Carroll would “roll over or something like that.”

Instead, Carroll lined the pitch, which was outside of the strike zone, into left-center for the first walk-off hit ... of his life?

“There's definitely been opportunities,” Carroll said. “But I can't remember, even through Little League, I don’t think I ever hit one so, pretty cool.”

The win was the 34th of the year for the D-backs, tying them with the Dodgers for most in the NL. They’ve also yet to be swept in a series this season, and after losing the first two games of a series against the Red Sox, they’ve won five straight.

The confidence continues to grow in the clubhouse, and the D-backs seem to be building momentum as the wins begin to stack up.

The schedule gets a little tougher for the D-backs as they have the NL East-leading Braves coming to Chase Field for a three-game series beginning on Friday.

“I couldn't be more proud of these guys,” manager Torey Lovullo said. “It was an awesome moment for me to watch and it was an awesome moment for this team to do what they did in the last inning down to our final out. 

“I'm going to think about this all night tonight. I know they will, too. And they should think about it and come out here tomorrow very refreshed and ready for an unbelievable series against the Braves.”