Ravens Nation has filled the city streets today, to jubilantly welcome home their victorious Super Bowl team. 

As in most cases when teams parade the Lombardi Trophy, the happy team is carried high through the streets, as thousands upon thousands of fans line the roads. 

It's never too cold when your team has just won the big prize.

So as the speeches are made and the players lap up the plaudits and celebrations, it won't be too long before the coaching staff get back into their offices and start plotting next season's title defense.

It won't be easy, as defending champion there is a massive target on your jersey.

So lets look at the five reasons why the Baltimore Ravens will not repeat this year's huge achievement.