When J.J. McCarthy got traded from the Vikings to the Giants, he called it "a shock" but also "an opportunity to take advantage of."

When Cam Skattebo received zero touches in Week 6 -- one week after a costly fumble -- he admitted he wasn't expecting the lack of involvement, but it also forced him "to kind of step back and look at it and figure out why."

Every NFL player faces pivotal moments -- make-or-break situations where they must dig deep and find a way to respond. Both challenges and opportunities in one. These were McCarthy's and Skattebo's. And in their biggest moments thus far in their young careers, they made their stand.

"I think that's exactly the story," John Harbaugh said about his team responding. "I mean to that's the point. It tells you who they are. You might have thought before the game 'We're gonna find out about our guys. We're gonna find out about who they are.' And we did."

In his first start with New York, McCarthy threw for 252 yards and had no turnovers, and in his return to prominence in the lineup, Skattebo ran for 124 yards and a touchdown as the Giants upset the Texans 27-21 in overtime. Skattebo's 42-yard rumble -- the longest run of his career -- set up Devin Singletary's walkoff score.

Before the overtime bursts, though, McCarthy put on a laser show against one of the NFL's most talented defenses. He smartly leaned on Malik Nabers (seven catches, 111 yards), who is looking very much like he's back to pre-ACL tear form, and made several truly outstanding throws.

McCarthy completed five throws of at least 15 yards downfield after completing six last week as a sub. The 11 completions are his most in a two-game span in his career ... and he didn't even sub in for Jameis Winston until the fourth quarter last week.

This is what the Vikings had hoped McCarthy would be when they drafted him: an athletic quarterback with a live arm able to access every part of the field. For McCarthy to do this, given the circumstances -- traded just weeks earlier, making his first start on the road against a really good defense -- was shockingly impressive.

"It's that thing: It's guys have scars," Harbaugh said. "He has scars. He's been wounded. He's been wounded. He's been battered. But you heal stronger, and you become better because of it, so you should be grateful." 

Skattebo, meanwhile, ran over, around and through Houston's defense. His 7.3 yards per carry represented the best of his career, and he credited the offensive line for opening up holes; his 65 yards before contact were the most in any game in his career. He also told the team's postgame show that he had ball security on his mind, which wasn't the case against Washington.

The common denominator between McCarthy's and Skattebo's performances? Harbaugh, the man who gave both players opportunities: Skattebo an opportunity to learn, McCarthy an opportunity, period.

The end of Harbaugh's time in Baltimore was defined by disappointment. After 18 years and a Super Bowl triumph with the Ravens, Harbaugh watched a Tyler Loop field goal sail wide in Week 18 last year, ending Baltimore's playoff hopes. He never got Lamar Jackson and co. over the hump. His reputation took a major hit in turn.

But perhaps it took too big of a hit. This coach has won 184 games. He won double-digit games 11 times in 18 years in Baltimore. That included his first year, when he turned a 5-11 team from 2007 to an 11-5 team in 2008. He knows how to build a winner and sustain a winner.

The early returns are that he's doing it again in New York. The Giants are 4-2-1, two wins ahead of anyone else in the NFC East. The Giants have won with Jaxson Dart, Jameis Winston and, now, McCarthy as starting quarterback. They're the first team since the 2016 Patriots to have three different winning starting quarterbacks within the first seven games of the year.

And this one meant as much as any regular-season win has. Just look at how Harbaugh reacted:

"I'm having a lot of fun," Harbaugh said, a smile coming to his face. "I'm having a lot of fun. There was a little dancing in the locker room."

McCarthy used that "fun" word, too.

"It was a lot of fun. So much fun to be out there playing football, but with this group, it makes it that much more fun, that's for sure."

And that's what these Giants were Sunday: fun. Fun to see McCarthy shining in a spot no one could have envisioned him in just a few weeks ago, when he was sitting on the Vikings' bench. Fun to see Skattebo ripping off big gains and Nabers making wild catches. Fun to see Abdul Carter and Kayvon Thibodeaux wreaking havoc.

Fun to see that, after losing their quarterback in Week 2, they're still playing well and still winning. Everything could have gone off course after Dart's injury. Instead, the Giants will head into their bye with their heads held high, in first place in their division and with meaningful football ahead.

"It's a reward," Harbaugh said. "Now you've got to make something of it. It doesn't mean anything if you don't build on it, right? Well, it means something, but it doesn't mean we're gonna win a championship yet. It means we have an opportunity.

"... We're gonna be in this thing until the end."

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