An entire season is on the line for Manchester United and Arsenal as they face off in a critical Barclays Premier League clash Sunday that is set to make US history.

This clash between two of the biggest clubs in the world also will become the first Premier League game ever to be broadcast live on free-to-air television in the United States. FOX will air all the action starting at 10:30 a.m. ET (check your local listings), before the NFC Championship Game between the New York Giants and the San Francisco 49ers.

The match pits two of the game's greatest managers, two of the world's hottest strikers, and two true heroes of the sport in a legendary clash. A win for Manchester United keeps the Red Devils within striking distance of defending their Premier League crown. A win for Arsenal not only would avenge the savage 8-2 loss the Gunners took against United in August but would keep them in contention for a spot in next year's Champions League -- and the massive riches that come with that.

The rivalry between the sides stretches back more than 100 years, but this one comes with a hefty side of modern, big-money politics. Arsenal long has been the team of wealthy London (the Queen is said to be a fan), while Manchester United historically has been the hardscrabble side with deep roots among Irish fans worldwide. Today, both are global brands owned by American NFL billionaires and are so grand that some of their club trappings seem almost quaint. United is the most valuable name in the world aside from the New York Yankees, and Arsenal isn't too far behind.

The teams' rivalry has cooled slightly, but that's not saying much. From 1997-2005 -- the era that made the teams' modern reputations -- it was open warfare. There was the so-called "Battle of the Buffet," the October 2004 match when United were accused outright of cheating in the 2-0 win that ended the unbeaten run of Arsenal's "Invincibles" at 49 games. After that match, United manager Sir Alex Ferguson was left covered in pizza after a food fight broke out in the tunnel, with Arsenal midfielder Cesc Fabregas said to be among the chuckers.

Rock bottom was hit when United's Roy Keane and Arsenal's Patrick Vieira went at it in the tunnel before a game in 2005 that resulted in a full-scale postgame brawl between the teams, the culmination of nine years of ill will, dueling news conferences, nasty put-downs and withering chants from the stands. Ferguson at one point had to beg his own fans not to call Arsenal manager Arsene Wenger a pedophile, which was on the tamer end of the scale.

But three years ago, Wenger memorably was sent to the stands at Old Trafford after kicking a water bottle along referee Mike Dean's touchline. Then, the Frenchman, surrounded by United's fans, seemed to see the humor, and he clowned around with the fans. The incident marked a thaw in the clubs' relations, and today the two gaffers claim to be friends -- but that might have more to do with Arsenal's notable lack of trophies since 2005. The notoriously competitive Ferguson probably doesn't see this bunch of Gunners as much of a threat.

With the wealth both teams command, one would think each could buy a title. They cannot, and in fact both are struggling with pressure from above and below, with Exhibit A being Manchester City, Exhibit B being Tottenham Hotspur. (Those two clubs meet in the preamble to Sunday's big game live on FOX Soccer at 8:30 a.m. ET.)

City has turned out to be particularly vexing for United. While the standings show that United is still in the Premier League chase, it doesn't show how humiliated the Red Devils are by the state of affairs.

City was once so poor that United didn't even deem the Blues a true rival despite being just 5 miles apart. No more: The so-called "noisy neighbours" have delivered a giant can of whoop-ass on United over the past 18 months and look to be the better team by some distance. Adding to United's woes was its collapse out of the Champions League -- to be fair, City also flopped in its first attempt at Europe's biggest club show -- and, in the season's lowest point, the Red Devils' ejection from the Carling Cup at the hands of Crystal Palace, a team stuck in the middle ranks in England's second tier.

Arsenal at least can say it's still in the Champions League, but this might be cold comfort considering that the Gunners, too, were eliminated from the League Cup (by City, no less) and had such an awful start to their Premier League campaign that the thought of a trophy win this season is laughable. In fact, a top-four finish is looking increasingly unlikely for an Arsenal side that has been exposed as lacking at almost every position. Bluntly, the Gunners have been saved by the fact that striker Robin van Persie is having a career year. Without the brilliant Dutchman in the lineup, the Gunners look like a team that can pass the ball, but neither score nor defend.

Such are the problems for both clubs that they went back to the future: Arsenal brought in former great Thierry Henry on loan from MLS' New York Red Bulls, while Ferguson persuaded 37-year old Paul Scholes to return in midfield. Both men were once legends, and they both enjoyed goals in their fairytale returns. But their presence, no matter how pleasing the nostalgia factor may be, points up a distinct lack of quality coming through the ranks.

Both teams, however, also have been ripped by injuries. Arsenal long has been without key midfielder Jack Wilshere , and the invaluable defender Thomas Vermaelen is absent again. Without those two men, so much pressure is placed on defensive midfielder Alex Song and attacking midfielder Aaron Ramsey that Arsenal are not able to break in their famous free-flowing counters.

Arsenal also has been badly let down by the regression of wide men Andrey Arshavin and Theo Walcott. Walcott is said to be seeking a pay raise, but that's unlikely considering he has had a string of dreadful performances. Arshavin's case is the more vexing. He looks like he is trying too hard, but his decisions can be baffling -- the fact is, he looks nothing like the brilliant player he was under Guus Hiddink for Russia.

United have lost three key men in defender Nemanja Vidic and midfielders Tom Cleverley and Darren Fletcher. But despite the fact that Scholes clearly has lost a step, the Ginger Prince already has made an impact, scoring in his debut start against Bolton last weekend. United needs all the help it can get in midfield, where it frequently looks careless in possession. But if there's one man Ferguson surely wishes he could bring back, it would be goalkeeper Edwin van der Sar, who retired at the end of last season .

Without Van der Sar in the net, United has gone from bad to worse. David de Gea was their big-money offseason signing from Atletico Madrid , and he's been rocky at best. Backup Anders Lindegaard is trying to make a case for himself as the starter, but he hasn't impressed, either. Part of the keepers' woes are clearly due to United's patchwork defense, but some of it seems to be the withering pressure at Old Trafford, where a keeper sinks or swims. Just ask Tim Howard.

The X-factor Sunday is none other than Wayne Rooney. When he is able to control the field of play, United wins games. When he is muzzled, United struggles to find its spark. Expect Song to play him tight. At the other end, while the cameras will be on Henry, everyone knows who scores goals at will. Expect Van Persie to get a rough reception from United defender Rio Ferdinand.