Am I right about this? (Structures, arrays, instances)

This is my code right now: http://pastebin.com/rN7ekgDd

It's just for fun and in order to learn using structures. Anyway, I have just run into something I don't really understand.

var premierLeague = League(name: "Premier League", country: "England")

var chelsea = Club(name: "Chelsea FC", country: "England")
var manUnited = Club(name: "Manchester United FC", country: "England")
premierLeague.teams.append(chelsea)
premierLeague.teams.append(manUnited)

premierLeague.match(homeTeam: &chelsea, awayTeam: &manUnited, goalsForHomeTeam: 4, goalsForAwayTeam: 0)
chelsea.statusInTable()
manUnited.statusInTable()
premierLeague.createLTable()

Alright. So I created an instance of structure League and then two instances of structure Club. Then I added them both premierLeague's array called "teams". So far so good I then let Chelsea and Manchester United play a match. The method "match" updated their statistics (number of played matches, victories/defeats and goals for them/against them).

On both chelsea and manUnited I then used method statusInTable() to show their statistics and it worked. Then I created a method createTable() in structure League and I decided to try it out. And suddenly, both teams had default values (0 everywhere).

I wondered what's wrong. Then I tried this:

premierLeague.match(homeTeam: &premierLeague.teams[0], awayTeam: &premierLeague.teams[3], goalsForHomeTeam: 4, goalsForAwayTeam: 0)

I called the method again and it worked!

I was honestly surprised. I think it has something to do with the value/reference types

My guess is that when I added "chelsea" and "manUnited" to that arrays, I added their copies and them themselves. So, while "chelsea" and "manUnited" were playing (and their statistics were changing), it had nothing to do with their copies in array "teams" (premierLeague.teams[0] and premierLeague.teams[3]).

And so, when I wanted to make a table from teams saved in array "teams". they had default values because I haven't been working with them.

Extra question: So, next time instead of this

var chelsea = Club(name: "Chelsea FC", country: "England")
premierLeague.teams.append(chelsea)

I should do this

premierLeague.teams.append(Club(name: "Chelsea FC", country: "England"))

unless I will need to use it somewhere else as well - right?