What does it mean "Cup tie"?
It's not a race for a tie
That you wear, or even
A score even-steven.
Aha! "bringing together" means "tie".

When people come together from all over for a "Cup tie", they are like strands which will be tied together in competition for days.

"Meet" is another word for "tie". When the meet is over, the tie is over. Competitors become 'untied' and they go their separate ways.

Note: "Tie" is a Britishism which we hear in North America in connection with the sport of tennis, primarily [I think, perhaps golf, as well]. Tennis originated in England so the Brits 'own' the vocabulary of the sport*, just as Americans, who invented the computer and the Internet, own the vocabulary of the computer and the Internet. [This last assertion could stir up a lively debate. :) ]

In North America, we call a sporting event a "meet", not a tie. As you are from the U.K., dxb, you may not be aware of that.

Now, where does even-steven come from?

From the Mavens' Word of the Day:

Question:

The other day, while doling out treats to my "kids" (my two Border Terriers) I uttered even-steven and then wondered where this phrase came from. Any ideas?

Answer

This is a rhyming compound meaning 'having settled accounts', as in "Give me $10 and we'll be even-steven." It also means 'having an equal score; tied', as in "The teams were even-steven." So it's just an emphatic form of "even." Also spelled even-Steven or even-Stephen, its connection with the male name "Steven/Stephen" is obvious. If this were the whole story, it would be considered an American English slang term from the 1860s. (Though it's now informal rather than slang.)

But other connections have been suggested.

http://snipurl.com/dfny

* The Russians appear to 'own' the vocabulary of pedology [an AWAD not long ago] because they did all the pioneering research in the field [of soil science].

The French appear to own the vocabulary of wine because they were the first to make the industry an art, which sounds like a contradiction in terms, but that's the whole point, isn't it?

Unfortunately for the French, French wine is losing its snob appeal, and, therefore, its market share world-wide. But we'll keep the French vocabulary anyway. We don't call the "Davis Cup Tie" the "Davis Cup Meet" just because the Brits lose to the Yanks. [Oops! I could be stirring up another debate. :) ]