NAPA Auto Parts has confirmed that it is to end its sponsorship of Michael Waltrip Racing's #56 car driven by Martin Truex Jr. at the end of the current season. The company had been in the first year of a three-year extension to their sponsorship deal with the team worth up to estimated $18 million per year that had been expected to last until 2016.

Truex was at the eye of a storm after the Chase decider at Richmond International Raceway after it emerged that the team attempted to manipulate the outcome of the race by having two of the other MWR drivers, Clint Bowyer and Brian Vickers, make extra pit stops in order to ensure an outcome that would see Truex make the title play-offs.

NAPA said at the time that it viewed the team's actions as "very concerning" and had questioned the team's "significant error in judgement," adding that it would review its sponsorship of the team, the outcome of which was announced on Thursday.

"After thorough consideration, NAPA has made the difficult decision to end its sponsorship arrangement with Michael Waltrip Racing," a statement on NAPA's Facebook page said. "NAPA believes in fair play and does not condone actions such as those that led to the penalties assessed by NASCAR. We remain supportive of the millions of NASCAR fans and will evaluate our future position in motor sports."

"Michael Waltrip Racing respects the decision NAPA announced today following the events at Richmond," the team replied in statement of its own. However, it insisted that it still planned to maintain its full line-up in 2014 despite today's setback.

"MWR has the infrastructure and support of Toyota for three teams plus three Chase-calibre, race-winning drivers," the team statement continued. "With the support of our corporate partners we are preparing to field three teams in 2014. MWR is a resilient organisation capable of winning races and competing for the championship and that remains our sole focus."

Ironically, the the driver and crew now hit most hard by the fall-out from the events two weeks ago at Richmond - Truex and the #56 team - were all completely innocent of any race manipulation charges, but has still ended up being booted out of the 2013 Chase as well as losing its main financial backing for 2014.

NAPA had been one of the few companies left in the sport that still acted as a car's primary sponsor for all 38 races of the Sprint Cup season. Its involvement with the sport goes back to the 1970s with track sponsorships, and began its Cup race sponsorships in 1995.

Nationwide ends championship-level sponsorship

Insurance giant Nationwide announced on Wednesday that it was to end its sponsorship of NASCAR's second-tier championship once the current seven-year deal expires at the finish of the 2014 season.

"We're proud of the success Nationwide Insurance has attained through our relationships with NASCAR and the Nationwide Series," said Nationwide's chief marketing officer, Matt Jauchius. "The NASCAR Nationwide Series is a great proving ground not only for drivers and crew members, but for sponsors too."

The announcement said that Nationwide would continue as NASCAR's official auto, home, life and business insurance partner of NASCAR through 2017 and will become the presenting sponsor of the Betty Jane France Humanitarian Award as part of a new, more consistent marketing focus on the NASCAR Sprint Cup Series beginning in 2015.

"It's a natural evolution for Nationwide Insurance to move our marketing investment to the NASCAR Sprint Cup Series and we'll continue to put tremendous effort behind all of our NASCAR marketing platforms in the years to come," said Jauchius. "We've been in this sport 14 years," he said, adding: "We're not going anywhere."

NASCAR's 'feeder series' began in 1982 with sponsorship from brewing giant Anheuser-Busch, which saw the championship called the NASCAR Busch Series until the 2008 season when Nationwide took over as naming rights sponsor in a deal reported to be worth between $8 and $12 million annually. NASCAR said that it was optimistic about quickly finding a replacement sponsor for the series.

"There will be very strong interest in this series entitlement position. There will be interest from some great companies, a lot of Fortune 500 companies. We will find a great partner for 2015, just like we did with Nationwide," insisted NASCAR's chief sales officer Jim O'Connell. "They were a fantastic partner ... They're obviously shifting their funds a little bit away from the entitlement, but they did a fantastic job for us, and we look forward to bringing in another partner."

All three naming rights deals of NASCAR's national-level championships are up for renewal in consecutive years, with Camping World needing to make a decision about their sponsorship of the Truck Series before it expires in 2015, and telecoms giant Sprint's entitlement contract with the Cup Series set to expire in 2016.