Cubs third baseman Kris Bryant got a lot of postgame attention Friday for his base-running — not to mention his home run in the seventh inning. And Gold Glove right fielder Jason Heyward got attention for a couple of nice catches — not to mention his game-winning hit with two out in the eighth to beat the Pirates 4-3.

But the most important development for the Cubs on their first day back from the All-Star break was the performance of their expensive, too-often-underperforming starting pitcher.

If it sticks. If he can back it up against the Reds on Wednesday.

That’s always the caveat when ultra-talented Yu Darvish has pitched well as a Cub — as infrequently as that has been.

Darvish hasn’t had consecutive quality starts since signing a six-year, $126 million deal before last season. But he also has never looked as good at Wrigley Field as he did Friday against a group of Pirates hitters who, barely a week ago, clobbered him and the rest of the Cubs’ pitchers for most of a four-game series.

“I told you guys last outing I’m almost 100 percent,” Darvish said of his confidence level after pitching six scoreless innings, allowing just two singles and a walk. “It’s 120 percent right now.”

He’s confident enough that when Cubs officials mulled the post-All Star break rotation, Darvish requested the crucial opener for a team that has no margin for error in a tightly clumped division as the front office plots its trade-deadline strategy.

“I think we all know what’s at stake here, and these next couple weeks are very important to us,” first baseman Anthony Rizzo said.

Darvish’s request carried a lot of weight in the decision to start him Friday.

“Last year, I didn’t do anything,” said Darvish, who pitched poorly and eventually was shut down because of elbow problems. “So I want to pitch a lot of games this year. I know that first game after the All-Star break is tough for the pitcher and everybody. But I believe I can do it, so I told [manager Joe Maddon] I can pitch.”

He didn’t get the decision and remains winless in 13 home starts as a Cub. But he also retired the first 13 batters he faced — and 15 of the first 16 — and didn’t allow a homer for the first time in six starts.

“He was outstanding,” Maddon said. “My God, anywhere, anytime, I’ll take that.”

The Cubs didn’t score until Darvish was out of the game, then blew a three-run lead on Starling Marte’s home run in the eighth before responding with Heyward’s two-out game-winner.

But this day was more about a pitcher who took a National League-worst 5.01 ERA into the second half.

If there’s one reason to think Darvish will trend well down the stretch, it might be the same reason behind his dramatic reduction in walks since early May (he has 17 in his last 11 starts after 33 in his first eight). He said the pain he felt last year throwing his fastball created mind games for him early this season until he finally trusted the pain wouldn’t return.

“I’m good now,” he said.

And if, by “now,” he means the final 2½ months of the season? What could that mean for this team?

“It goes without saying,” Heyward said.