FONTANA, Calif. — A new teammate and rules package have given Ricky Stenhouse Jr. a clean slate — and he’s capitalized on it.

In the first four races of 2019, the No. 17 Roush Fenway Racing driver has finished no worse than 18th, including a season-best, sixth-place effort at Las Vegas. In contrast, Stenhouse Jr.’s best finish in the first four events in 2018 was 14th, with a result as low as 29th.

Stenhouse Jr. hopes the uptick in performance continues during Sunday’s Auto Club 400 at Auto Club Speedway where he’ll start 12th (3:30 p.m. ET, FOX, MRN, SiriusXM NASCAR Radio).

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“We did expect it,” Stenhouse said. “We knew these cars fit my driving style maybe a little bit better. But we also knew it was kind of an opportunity to kind of close the gap on the competition.”

While Stenhouse Jr. has thrived with the new aero package, it’s still been a seesaw for him and new Roush teammate Ryan Newman as each race has presented a different set of challenges for the entire Monster Energy NASCAR Cup Series field – something he anticipates will continue.

“We’ve done a good job this offseason taking steps in the right direction, but I think every race this year, you see teams kind of go up and down — gain speed, lose a little bit of speed,” Stenhouse Jr. said. “So, I think it’s going to be kind of a cat-and-mouse game I feel like for the first half of the year. Everybody just trying to figure out what package and how much downforce they’re going to bring to the race track on that given weekend. Definitely a good start for us and want to keep that going.”

Like Matt Kenseth last season, Newman has brought valuable information and unique, veteran feedback to the table to help steer the Roush ship in the right direction. Stenhouse Jr. feels he and Newman have a strong relationship both on and off the race track — which has allowed the organization’s gains to flourish even more.

“I like Ryan,” Stenhouse Jr. said. “I think Matt and I said a lot of the same things in different ways, kind of like Ryan. He talks way different than Matt did and any teammates I’ve ever had. Some of that comes from a little bit more engineering-minded driver, which you don’t have many of. So, I’ve never had a teammate like that. To listen to him talk about and kind of pick apart the car in different ways has been kind of cool.”

While both drivers have enhanced speed in their Ford Mustang fleet, Stenhouse Jr. has also muscled his way to finishes – making headlines for rubbing multiple drivers the wrong way from time to time in the year’s early races. But the 31-year-old says his driving style hasn’t changed, nor will he alter it.

“I’ve got a car better to work with and (I’m) able to do different things with it,” he said. “For me, I feel like I’ve always driven the same, it’s just depending on what situation that I’m in, depending on what I want to do. So, I’ll always race hard.”

It’s that type of driving style that gives Stenhouse Jr. and Newman something in common. But according to Stenhouse Jr., it’s not so much Newman’s aggression that makes him notoriously tough to pass.

“Everybody says that Ryan’s hard to pass, but I’ve always told Ryan I feel like he’s hard to pass because he doesn’t make mistakes,” Stenhouse Jr. said. “He’s got the same mentality – if you’re faster, pass me. Go around me, run (a) different line than I am. But the reason he’s so hard is because he never messes up.”

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If that mentality sounds familiar it might be because that’s exactly what Stenhouse Jr. said following his battle with Martin Truex Jr. late at Atlanta. It’s actually Stenhouse’s goal to develop the trait that Newman currently possesses — being hard to pass because you don’t mess up.

“I want to get in that position where I don’t make mistakes because I feel like that’s helped Ryan throughout his whole career,” Stenhouse Jr. said. “He might not have a 10th-place car running 15th, but he never makes mistakes and so he kind of grinds out good finishes. I think that’s a good trait to have.”