Chelsea Cup

Why does Chelsea play Portsmouth in the FA Cup final?

I’ve only been into EPL for about a year now, I am still new at this. I know what Champions League is, I know was UEFA is, but I am curious about FA cup, why is the #1 team playing the worst team for this cup?
I just think it’s odd that’s all. So, any team from England, even ones not in the EPL can be in the FA cup?

the FA cup is a trophy within England, with 300 teams competing, as you would guess there are some terrible teams, much, much worse than portsmouth, anyway, the prem teams (such as chelsea and portsmouth) come in at the third round and they play any team that they are randomly drawn against, here is a few notable results (the FA cup is knockout btw)

Manchester united 0-1 Leeds United
Arsenal 3-1 Stoke City
Liverpool 2-3 reading

get the picture? Premiership teams can also be drawn against each other such as the semi finals were…

Chelsea 3-0 Villa
Portsmouth 2-0 Tottenham

portsmouth had to beat… tottenham, birmingham coventry sunderland and southampton

Chelsea had to beat… villa, stoke ,cardiff ,preston ,watford

Hope this answers your question

Manchester United 4-0 Chelsea (Agg 6-3) – FA Youth Cup Semi Final – 20-04-11