While NASCAR fans delighted in a series of highlights in 2011, they also witnessed their share of low points. Fans witnessed feuds that reached new heights, temper tantrums by so-called professionals and continued sponsorship problems that led to the loss of jobs for many in the industry.

Although the Sprint Cup Series enjoyed 18 winners this season, two of those drivers found themselves grabbing additional headlines of an unwanted nature, and the sport’s most popular driver watched his victory drought swell.

All in all, several stars are probably ready to put this year behind them. What were the worst moments of NASCAR's 2011 season?

Kyle Busch certainly had a memorable season, but not the kind he and team owner Joe Gibbs envisioned.

It started with a series of confrontations between Busch and Kevin Harvick. At Darlington, Busch spun Harvick on the track, and then Harvick confronted him on pit road. Busch pulled away, pushing aside Harvick’s empty car, which then rolled down pit road.

A few weeks later, Busch got into it with Richard Childress Racing’s Joey Coulter, a move that resulted in a post-race altercation between Busch and Richard Childress.

Not long after, Busch found trouble off the track, being ticketed in North Carolina for driving 128 mph in a 45-mph zone.

Then came perhaps the final straw, when Busch intentionally spun title contender Ron Hornaday in the Camping World Truck Series. At that point, NASCAR parked Busch for the Nationwide and Sprint Cup races at Texas, Busch lost M&M’s sponsorship for the final two races of the season and he dropped out of the top 10 in points.

Not exactly the type of season Busch probably envisioned back in January.

Kurt Busch, like his brother, found himself among NASCAR’s chief bad boys in 2011.

Busch’s vitriolic radio rants toward his own team caught the attention of both fans and media. But that was only part of the story.

At Richmond in September, after qualifying for the Chase for the Sprint Cup, Busch went off on a pair of media members that ended with the driver ripping apart a reporter’s paperwork in a move captured on a live streaming feed.

Later, at Homestead-Miami Speedway, Busch tore into a reporter who was waiting to interview him in the garage, an expletive-filled commentary caught on video by a fan and posted on YouTube. When that went viral, Busch issued an apology, NASCAR issued a penalty and Penske and its sponsor issued statements expressing their displeasure.

In December, Busch and the team announced they had mutually agreed to part ways, with Busch setting no firm plans for 2012.

The economy continued to impact NASCAR in 2011 in terms of team sponsorship.

Several top teams find themselves seeking backing for 2012, and the Red Bull Racing organization (whose cars are pictured above) has closed its doors. The Red Bull decision effectively discontinues two Cup teams that have won in recent years, most recently Kasey Kahne at Texas in November.

Richard Childress Racing is reducing its Sprint Cup teams from four to three, and Roush Fenway has reportedly laid off employees. In addition, the future of Roush Fenway's No. 6 team is in doubt, and its No. 17 team — driver Matt Kenseth contended for the title this season — is preparing to run in 2012 without full sponsorship.

And then there's the issue of the various crew members who have been laid off since the season ended.

Dale Earnhardt Jr. is the nine-time, fan-voted Most Popular Driver in NASCAR. He’s also a guy desperately searching for a win.

While he did return to the Chase for the Sprint Cup this season, Earnhardt’s many fans are hungering for a win. Their hearts were broke when he ran out of gas on the final lap of the Coca-Cola 600 in May. He ended up closing the year still seeking to end his winless streak: It stretches back to June 15, 2008, and includes 129 starts without a win.

This was supposed to be Bruton Smith's moment to shine was chairman of Speedway Motorsports Inc. After years of pursuing a Sprint Cup date, and a legal challenge to get it, Kentucky Speedway had finally snared a Cup race date.

Thrilled fans poured into the track for the debut event. At least, they tried to. A variety of issues snarled traffic for hours and left passionate fans maligning the track’s effort throughout that day and in the ones to come. Both the track and NASCAR have vowed those issues will have been addressed when racing returns to the track in 2012.