It's pretty simple to Gibson, really.
"The key is to get the bases loaded," Gibson said. "I hope we get to come back here and maybe do it for the fifth time."
That, of course, would be in the National League Championship Series, which would take a Game 5 victory in Milwaukee to make happen.
Having provided bookends to the grand-slam streak, his Sept. 27 bomb getting it started, Roberts said the D-backs have done what you're supposed to do when batting with the bases loaded.
"In that situation, you talk about not trying to do too much," Roberts said. "You just try to put a good swing on the ball, not try to hit the ball out, not try to do too much. I think everybody's done that, and it's happened to go out."
One night after rookie Paul Goldschmidt delivered a grand slam to lead the D-backs to a Game 3 victory, Roberts turned on a Randy Wolf changeup, sending it into the home bullpen in left field and sending the black-clad D-backs crowd into a rafters-shaking frenzy.
According to the Elias Sports Bureau, it marked only the second time in postseason history a team has delivered grand slams in back-to-back games. In the 1977 NL Championship Series, the Dodgers' Ron Cey collected one in Game 1 and Dusty Baker followed with one in Game 2. The D-backs became the fifth team in postseason history to collect two grand slams in a single playoff series.
Chris Young followed Roberts' shot with a home run to center field, providing the D-backs with the first back-to-back homers in their postseason history.
The streak of slams began with the remarkable Sept. 27 walk-off shot by Roberts against the Dodgers, a feat that was only the fourth extra-inning grand slam in history to erase a three-run lead, putting him on the same list with Babe Ruth (1925 Yankees), Roger Freed (1979 Cardinals) and Jason Giambi (2002 Yankees).
On that one, Roberts did his best Gibson impression, circa the 1988 World Series, pumping his fist as he circled the bases. This time, a curtain call -- the second in as many nights for a grand-slam performance -- brought him to the top step of the dugout, where he waved his arms wildly in celebration with the fans.
"I'll take both of them," Roberts said. "Both are equally as meaningful to me. I can't say one's better than the other. They're both special to me."
Roberts' regular-season slam, the first of his career, was followed on the season's final day by a Cole Gillespie grand slam in the ninth inning of a 7-5 loss to the Dodgers. Now, two more in the postseason have pushed the team to the brink.
Before Game 4 on Wednesday, Gibson spoke about his team's recent propensity for coming through with the bases loaded.
"I hope there's another one for us. Those are nice," Gibson said.
He and the D-backs got their wish in the first inning, and that started with leadoff hitter Willie Bloomquist delivering yet again. He has reached base to lead off the first inning for the D-backs in three of the first four games, being tagged out at home in Game 1, scoring the game's first run in Game 3 and then standing on third when Roberts unleashed his shot Wednesday night.
"If I can get hit by a pitch or walk or get a base hit, just somehow get on base to get us going and jump-started, that's my job," Bloomquist said.
And in Game 4, it couldn't have ignited the first salvo of the game any better, as the D-backs continued their run of truly grand performances.
"That's a tribute to guys getting on base and guys doing damage when they are on base," Bloomquist said. "We've done that all year. It seems to be timely hitting at the right time. That's what makes this team fun. It's somebody new all the time."
But four grand slams in four home games? That's kind of crazy.
"This team's been great all year like that," Roberts said. "It's just coincidence that it happened so fast."