Column: Final stretch shouldn’t be perilous for Dodgers but ...

Yasiel Puig flung his bat and flexed his muscles as he rounded the bases.

Once he touched home plate, he waved his arms upward as if to urge to the fans to make more noise.

They couldn’t.

Dodger Stadium was literally shaking. The noise was already at postseason levels.

Puig’s three-run, pinch-hit home run broke a seventh-inning stalemate and vaulted the Dodgers to a 5-2 victory over the Colorado Rockies on Wednesday night that completed a three-game sweep in the single-most important series of their season.

October is almost here and in more than one way. With nine games remaining in the regular season, the Dodgers have a 2 ½-game edge over the second-place Rockies. They are on the verge of claiming their sixth consecutive National League West crown. A place in one of the NL’s two division series is all but theirs.

If they can beat the San Diego Padres first.

If?

Well, this is 2018, and if there’s a collection of Dodgers who can blow a 2 ½-game lead in a week and a half, it’s this group.

The Dodgers have already experienced plenty of unexpected crashes.

“Tell me about it,” said closer Kenley Jansen, who pitched a perfect ninth inning Wednesday to earn his 36th save.

The final stretch shouldn’t be perilous, with the Dodgers hosting the Padres this weekend, then visiting the backsliding Arizona Diamondbacks and whatever remains of the San Francisco Giants dynasty.

But consider how the Dodgers have won seven of their last eight games, reflect on the stop-and-go nature of their season over the previous 5½ months and the upcoming home series against the last-place Padres that opens Friday starts to looks suspiciously similar to a trap door.

“We know it’s going to be a tricky series against the Padres,” Jansen said. “They don’t care. They’re already planning their vacations. We need to come out there and swing and don’t take [our foot] off the gas pedal.”

The Dodgers have proved they can win the important series.

They transformed a 1½-game deficit to the Rockies into a 21/2- game lead by taking three of four games in St. Louis from the wild-card contending Cardinals and claiming three consecutive home games against the Rockies.

The problem is what’s followed their greatest triumphs.

“When you’re a talented team where you know you can turn it on any time you want, that kind of gets in our way, I feel like,” Jansen said.

The last time the Dodgers were alone in first place, on Aug. 7, they promptly surrendered their perch to the Diamondbacks by dropping six of their next seven games, including a pair to the would-be-in-last-place-if-not-for-the-Padres Giants.

Or take what the Dodgers did when they started this month by winning three of four games against the Diamondbacks and two of three in Colorado. They lost the first two games of a three-game series in Cincinnati to the last-place Reds.

Yeah, that really happened.

These unexpected breaks in momentum have prevented the Dodgers from embarking on the one- or two-month tears that have become the norm in recent years. Their current division lead is their largest of the season.

“It’s not that we turned it off,” Jansen said.

Jansen pointed to the injuries that sidelined him, Justin Turner and Clayton Kershaw. He mentioned the slumps that endured by various players, including himself.

“I think this year it was such a battle for all of us,” Jansen said. “Things were tougher this year. You see us play, we always battle. It’s not like we just turn the switch on. It’s just that we find it at the right time.”

The Dodgers were 1-6 against the Reds. They were 2-4 against the Miami Marlins, another last- place team. They are 7-9 against the Giants, whom they will visit for their final series of the regular season. They have at least dominated the Padres, against whom they are 12-4.

“We’ve got to keep our foot on the gas right now,” Jansen said. “We’re talking about, what, nine games left? We’re not asking for a lot.”

The Dodgers have won 12 of 16 games in September, making this their best month of the season.

Manager Dave Roberts sounded hopeful about his team’s chances of sustaining its current form. “These are playoff games,” he said. “I think you can see the intent on every single pitch. We smell the finish line of the regular season. There’s a lot of sacrifice going on. The preparation hasn’t wavered. The bottom line is we have very good players.”

That was never in question. Their ability to play like it consistently has been. They have to do that now.

dylan.hernandez@latimes.com

Twitter@dylanohernandez