Simon Pagenaud still thinks about how close he came to defending his NTT IndyCar Series championship in 2017. He shakes his head with a slight wince of pain at the thought of it.

The Team Penske driver lost the title by 13 points two seasons ago to teammate Josef Newgarden, who soon learned that staying on top is that much more difficult. Newgarden was unable to repeat as well, finishing fifth last season as Scott Dixon of Chip Ganassi Racing took home the Astor Cup for a fifth time.

Pagenaud suggests the difference from one year to the next can be so miniscule, be it fractions of a second at a particular race or just bad luck on an unforgiving day as opposed to a fortuitous escape or ideal caution flag at an opportune moment.

“It’s almost like you wake up one day and you get on the road and every light is green, right?” Pagenaud said. “So you get to your job and your work five minutes early. The next day, you get up and everything is red and there’s traffic everywhere and it’s raining and you can’t get there on time. You didn’t do anything different.

“That’s why racing is so beautiful. We try to make it scientific, we try to understand everything in the labs, we try to get the car fast the same way every weekend, but the wind is different, the temperature changes and the outcome around you changes, the engine changes and it’s different. That’s why it’s so difficult to repeat.”

That’s the challenge ahead for reigning champion Dixon as the 2019 NTT IndyCar Series season resumes this weekend with the INDYCAR Classic at Circuit of The Americas. Dixon has won the title five times but reminded throughout the offseason that he’s never gone back-to-back, either.

The last driver to do so was now-retired Dario Franchitti, who won three championships in a row from 2009-11.

“Hopefully he can help me a little bit with that scenario,” Dixon said of Franchitti, his close friend who still works for Ganassi as a driver coach. “Yeah, you know it’s always tough with the competition throughout the field and the small differences between the teams now. There are no small teams. There are no very average drivers anymore. Consistency definitely plays a big part to try to win another championship.”

Chip Ganassi spoke before the season of his role to ensure Dixon has the best possible chance to repeat. In addition to Franchitti, the team owner saw driver Alex Zanardi win back-to-back crowns in CART in 1997-98. As a team, CGR has twice had four-peats, from 1996-99 in CART (with Jimmy Vasser in ’96 and Juan Pablo Montoya in ’99 sandwiching Zanardi’s double) and 2008-11 in the NTT IndyCar Series (Dixon in ’08 ahead of Franchitti’s three-peat).

“We’ve had times where we defended our championships with another championship and we’ve had times where we haven’t,” Ganassi said. “I wish there was something I could say we did wrong or did differently or should have done differently. People don’t realize when you win a championship how small the differences are, that extra tenth of a second at a particular track, on a particular day, how much that turned into by the end of the season. A tenth of a second, somebody is willing to work for that extra tenth.

“When you beat people consistently like Scott has done, that has the tendency to energize them to work even harder. And believe me, they are working hard to beat our team and him as a driver. That means we have to work harder. It’s up to me to keep that fire burning in their bellies, in the team’s bellies, so they want to work harder, so they give Scott the car so he can get that extra tenth here and there during a season that means so much that you really don’t see when it comes to the end of a season.”

What’s great about Dixon, Ganassi said, is the 38-year-old New Zealander is never satisfied. He always wants more.

“Me, too,” Ganassi added with a smile.

Dixon got off to a promising start, finishing second in the 2019 season opener on March 10, the Firestone Grand Prix of St. Petersburg. By comparison, in his last three championship years (2013, ’15, ’18) when the season opened in St. Pete, he never finished better than fifth. He did begin his 2003 and ’08 title pushes with a season-opening victory on the Homestead-Miami Speedway oval.

Newgarden echoes Pagenaud in the belief that he didn’t drive any differently last season as compared to his championship year in 2017. He just wasn’t as “consistent.” That word comes up, well, consistently, in this conversation, especially when analyzing how Dixon is typically the best in maintaining such a high level of performance throughout a season.

“We did the same thing last year,” said Newgarden, who along with Dixon and Will Power tied for the series lead with three race wins apiece. “We came up short, obviously. We just weren’t consistent enough last year. Particularly, Scott was very consistent. I want to say he was the strongest across the board, but for consistency, no doubt, he was on another level.

“You can have wins and you can have really streaky moments where you’ve been really quick, (but) if you don’t have that consistency throughout the year, then you’re not going to probably challenge for the championship.”

Newgarden began his challenge to unseat Dixon as champion by winning the season opener at St. Pete. He takes a 13-point lead into this weekend’s race in Austin, Texas.

After finishing runner-up to Dixon in his best series season yet, Andretti Autosport’s Alexander Rossi hopes to break through in his fourth season with a first championship. Rossi knows Dixon well. They pushed each other to a last-race showdown for the crown in the 2018 championship chase.

“It's a competitive championship, as we've all said, and it punishes mistakes, even small ones, so I think we've just got to continue hopefully our development that we saw from 2017 to 2018 and carry that forward to (this season) and just be more consistent across the board, and hopefully that will be enough,” Rossi said.

Then the 27-year-old Californian added, with a chuckle, “But I'm sure Scott will continue winning races, and he's won like 100 now (actually 44), so he'll be hard to beat until he stops racing, which I hope is soon.”

The INDYCAR Classic weekend at COTA begins with three practices on Friday, starting at 11:15 a.m., 3:05 p.m. and 4:10 p.m. ET. A fourth practice is set for 11 a.m. Saturday. All practices stream live on INDYCAR Pass on NBC Sports Gold.

NTT P1 Award qualifying to determine the pole sitter and the starting grid airs live at 3 p.m. Saturday on NBCSN, NBCSports.com, the NBC Sports app and INDYCAR Pass on NBC Sports Gold. The first NTT IndyCar Series race at Circuit of The Americas airs live at 1 p.m. Sunday on NBCSN, NBCSports.com and the NBC Sports app.

Tickets for the race weekend are available on the COTA website.