The frustration is evident in every word Greg Biffle speaks about the troubled 2014 season that he and Roush Fenway Racing endured.

He and now-former teammate Carl Edwards made the Chase for the Sprint Cup, but Roush as a whole struggled to keep up with the frontrunners.

Reflecting on last season, Biffle – who himself went winless and was eliminated in the opening Challenger Round – is very blunt.

“I tell you that last year was probably the toughest year of my life ever,” Biffle said recently in a one-on-one interview with NASCAR AMERICA’s Marty Snider. “Words can’t explain how frustrated, at times humilated, [I was about] how [I was] running … The frustration level that we could be this far off-course. And you know what? It’s not for a lack of effort.

“We worked harder last year as an organization than the [No. 4 Stewart-Haas Racing team] that won the championship. We worked harder. We were there seven days a week, all hours of the night. Testing, building new equipment, trying new cars. We never gave up.

“And it killed us. It killed our people. It killed us as drivers. We’re going right from one race track, testing for three days, going straight to the next race track – not even going home. We never got any better. We actually, at one point, got worse.”

Over this off-season, the Roush camp has left no stone unturned in trying to find what has been hurting their performance. And Biffle says they have diagnosed and corrected some of those problems – giving them hope that they can return to Victory Lane and contend for a championship in 2015.

You can watch Biffle’s full interview in the clip above.

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