Celtic in Champions League Last 16: 5 Reasons It's Good for Football

Celtic made it through the group stages of the UEFA Champions League this week with a late-winning goal against Benfica, good enough to secure them the second spot in Group G behind Barcelona. It was a victory for the underdog and the unexpected, which will give heart and hope to teams in future events of the competition.

The knockout stages of the Champions League will be dominated by teams from some of the biggest footballing nations: four teams from Spain, three from Germany, two from England and Italy and one apiece from Ukraine, France, Turkey, Portugal—and, of course, Scotland.

Celtic will be the smallest (in terms of recent relative continental success) and least-fancied representative left in the competition, but their continued presence is a great thing for the best competition in the game.

Here are the top five reasons why football should be glad that Celtic survived the group stages and will compete in the knockout rounds.

Celtic Park is a real cauldron when it's full, the occasion is a special one and the fans get right behind their team.

Few fanbases can back their side quite as well as Celtic's can at times. Their green-and-white scarves, tops and flags is a truly magnificent sight, made all the bigger as it appears to extend from the pitch to the uppermost corners of the stadium in the same resplendent shade.

For supporters in the stadium, it is a moment to savour. For the viewer on television, it makes the Champions League seem very much a personal and memorable experience, even from a distance.

Half-empty stadiums around Europe are becoming too commonplace for the good of the game, but Celtic Park will be full to the rafters for the remaining Champions League matches that take place there.

Scottish football needs the Glasgow derby.

With the Rangers having been relegated to the Scottish Third Division this season and needing to slowly make their way back up the league ladder, the Scottish Premier League is in danger of becoming  irrelevant to all but the most passionate and loyal of football lovers outside of the country.

Watching rivals make waves in the Champions League to the tune of extreme financial and sporting gain will be a tough, bitter pill for the blue half of the city to swallow, but it will also make supporters even more determined to put things right as soon as possible—from their own perspective, that is.

Rangers supporters expect their team to bounce back in consecutive seasons and then to challenge once more, after a time, for SPL supremacy.

Celtic's successes will remind Rangers of what they have previously fought for and ensure they do everything possible to be similarly involved again at the top end of the game.

For all those big nations that will have participants in the Champions League during the knockouts—almost 70 percent of the remaining teams are from the "big four" leagues—Scotland and Celtic have shown again this year that there is still room amongst the elite for an underdog.

With neither the best domestic league nor even the most talented or expensively assembled squad, Celtic have nonetheless performed well enough over six games to warrant their spot in the latter stages of the competition.

Financial rewards are as important as the sporting ones—there is no reason to pretend otherwise—and if invested wisely can bring the increased possibility of repeating the feat in years to come.

It also will do some good for the team's—and in turn the nation's—UEFA coefficient ranking, thereby helping the domestic league to retain its spot in the Champions League and Europa League.

Ukraine, Greece, Romania and Belarus saw their representatives end in third place this season. Scotland's finest have shown that the smaller sides and nations can go one better and prove themselves good enough to make the knockouts.

Barça fans, take it as a backhanded compliment.

They didn't win the Champions League or La Liga last season, but by common consent, Barcelona are still the team to beat in Europe.

Tito Vilanova's side are going strong at home and abroad, being undefeated domestically so far.

Celtic of the SPL, however, have beaten them in the Champions League and went mightily close to taking a point from the Nou Camp too.

They might have been defensive, nowhere near as good technically and absolutely battered in terms of possession, but Celtic found gaps, exploited them and took advantage of the chances they created to win the games.

And in the end, that is the most important thing in football.

Other teams will take note and try to replicate certain instances to help them defeat Barcelona when they come up against them.

Football is big business.

There is no need to mistake Celtic's fortune and hard work for anything other than what it is—they are the underdog remaining in the Champions League for a reason.

Sure, they beat Barcelona, Spartak Moscow and Benfica.

But every other team in the competition would fancy its chances of defeating the Scottish side over two legs.

Celtic will be drawn to face one of the seven other group winners in the round of 16, and you can guarantee that every club would be happy to be paired with them.

They'll put up a great fight, will be tough to beat and if they get through any further will surely deserve it—but every team will want to play Celtic because they are almost certainly the weakest side left in the competition and therefore offer the best chance for everybody else to progress.

It might not turn out that way, and the Scottish side's achievements will be all the more remarkable for it but as of right now they are definitely the team that seven clubs want to be playing in the first knockout round.

Follow @karlmatchett