After the opening weekend of the World Cup many sides will now have got an idea of just how difficult it will be to win the tournament in New Zealand.
This includes the four home nation sides that will certainly have mixed emotions after their first set of results.
England, Ireland and Scotland all gained victories but it wasn't the way they would have liked it, while Wales fell to defeat despite playing the best rugby out of the four sides.
Obviously, it's still early days in the tournament and teams will be expected to get better as it progresses, but what have we learnt from the home nations opening games?
One thing for sure is that the minnows of the rugby world aren't going to roll over easily as Scotland and Ireland found out.
The Scots took on Romania in the early hours of Saturday morning and it was a game they were expected to win comfortably, but this was not the case.
With only 13 minutes to go Scotland were three points behind but a Chris Paterson penalty followed by two Simon Danielli tries ensured a 34-24 bonus point win.
Andy Robinson's side looked patchy as the forwards were constantly being beaten, which will make the English, Argentinian and Georgian packs very happy.
Despite the poor handling and game management up front Scotland did the most important thing which was to win the game.
But a huge improvement is needed especially in the forwards as they prepare for their next game against Georgia, which once again they should win with ease.
Meanwhile, Ireland toiled to a 22-10 win over the USA which wouldn't have impressed too many Irish fans.
The USA national team, nicknamed the Eagles, are currently ranked 18th by the IRB World Rankings and they should have been overwhelmingly beaten by Ireland.
But they defended aggressively and frustrated the Irish side which will raise some concern for coach, Declan Kidney with upcoming games against Italy and Australia.
Another decision for the Irish coach is whether Jonathan Sexton or Ronan O'Gara will start in their next match.
Sexton didn't find his kicking range against the USA and he lost the side some valuable points, which was reiterated when O'Gara was brought on after 50 minutes.
The issue for the Irish side seems to be finding consistency because on their day they can play well enough to give any team in the world a hard time.
Ireland captain, Brian O'Driscoll knows there is a lot of improvement needed, he said: "We didn't play well and we really had to fight for our win.
"I suppose it's job done but we've got a hell of a lot to improve on. Our set-piece was very good but we turned ball over way too much and didn't get any continuity.
England are the side considered to have the best chance of going all the way from the four home nation sides, but they also made the shakiest of starts against Argentina in Dunedin.
Martin Johnson's side edged out the Pumas 13-9 in a very tight affair which could have gone either way.
Argentina's highly competitive and committed players once again showed they were becoming a force in world rugby, and if they had not missed six penalty attempts it may have been a different story.
English nerves were put at rest in the 66th minute when replacement scrum-half Ben Youngs went over to drag England from the brink of defeat.
It was the same old problems for England as they gave away far too many penalties with Nick Easter being at the forefront, and Dan Cole was also sent to the sin-bin.
Johnson will know that his side need to cut these mistakes out quickly because a side with a better goal kicker will make them pay.
It was a bad night for Jonny Wilkinson too as he missed four consecutive penalty attempts and England continued to lack imagination.
Maybe Toby Flood will get a chance against Georgia, but either way the win against the Pumas should mean another victory over Scotland on October 1 will ensure England finish top of their pool.
It was never going to be an easy task for Wales as their first game was against World Champions, South Africa.
After 12 years of trying, the Welsh came within a whisker of beating the Springboks after they gave a performance of great determination and desire.
Warren Gatland's side looked to be much better for most of the game and they may even complain that they were robbed after James Hook's penalty was ruled not through the posts, although replays showed it may have done.
The blow for Wales came when replacement Francois Hougaard, on for Bryan Habana, found a gap and scored under the posts.
It was a huge blow for Wales after such a encouraging display, but they will have learnt that closing a game out when you're on top is vital.
When the final whistle came, Wales knew they had squandered yet another second-half lead against the world champions, as they have done in their last three meetings.
The next round of games will give us a good view of how the sides have learnt from their mistakes, which they will be expected to do.
There is no doubt that all four nations will continue to learn and improve in the tournament, but in a World Cup situation it has to be done quickly or you could be staring at elimination.