Executing trades in the NFL is a tricky business.

Each transaction that’s carried out in Pro Football comes hand-in-hand with at least a certain level of risk, as team finances and the reputation of the front office come firmly into question.

It takes guts to swap a player on your current roster for an unpredictable set of draft picks, but it happens fairly regularly nowadays – as showcased by the Philadelphia Eagles,who shipped out three players to Miami and Nashville just this week.

The reason is simple. If the trade comes off, it can act as a speed boost to the top, and it has done on many occasions.

But much more often, trades fail miserably, and franchises are left to dwell on what might have been if they’d kept hold of the valuable draft picks they gave away.

Lots of trades go by relatively unnoticed, but some have changed the football world into what we know and love today.

Here are five trades that changed the National Football League forever.

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