UPDATE: After the Union's Meet The Team event and third jersey unveiling Tuesday night, I was able to put a few more pieces of the puzzle together. The roster now stands at 29 players, as far as I can tell, with the inclusion of Matt Kassel. So the Union have one "off-budget" player slot left. All 20 of the "on-budget" slots remain occupied.

With four days to go until Major League Soccer's roster compliance deadline, the Philadelphia Union made what may have been their final two cuts of the preseason.

Spanish midfielder Jordi Vidal - who manager John Hackworth said impressed the team in training camp - and Bulgarian forward Georgi Hristov are no longer with the team.

You may remember that last week, Hackworth said his decision about Vidal's future was going to be difficult. But the writing was on the wall for the Real Madrid youth academy product, and in the end he did not make the final squad.

The Union must be compliant with Major League Soccer's 30-player roster limit and approximately $2.95 million salary cap by March 1. By my count, the team's roster now stands at 29 players:

(Note that these are not jersey numbers. They're just names listed in alphabetical order, with numbers attached for counting purposes.)

1. Don Anding
2. Freddy Adu
3. Chris Albright
4. Brian Carroll
5. Conor Casey
6. Danny Cruz
7. Keon Daniel
8. Gabriel Farfan
9. Michael Farfan
10. Leo Fernandes
11. Raymon Gaddis
12. Chase Harrison
13. Cristhian Hernández
14. Chandler Hoffman
15. Antoine Hoppenot
16. Greg Jordan
17. Matt Kassel
18. Chris Konopka
19. Michael Lahoud
20. Sébastien Le Toux
21. Zac MacMath
22. Jack McInerney
23. Jimmy McLaughlin
24. Amobi Okugo
25. Jeff Parke
26. Bakary Soumaré
27. Roger Torres
28. Aaron Wheeler
29. Sheanon Williams

In case you're wondering why Zach Pfeffer and Carlos Valdés aren't on the list, it's because their season-long loans abroad mean they don't have to count against the Union's roster limit.

With that said, the Union have two roster spots open. But when you start to look at where the Union's payroll money will be going this year, it's fair to wonder whether those spots will be filled.

We won't have this year's salary figures for a while yet, but if you look at last year's numbers you can get a few indications of where the Union were starting from this offseason. Then add in Casey, Le Toux and Parke. All three are veterans, and as such would not have come cheaply.

There are a few other factors as well.

First, only $368,750 of Adu's salary counts against the cap, as is the case with all Designated Players. Second,

Second, and of no small consequence too, a source confirmed to me late Monday night that three Union players graduated from Generation Adidas during the offseason: Zac MacMath, Jack McInerney and Amobi Okugo.

This means that the Union are on the hook for the entirety of all three players' salaries for the first time.

Chandler Hoffman is now the only Generation Adidas player on the Union's roster.

Here is where things start to get complicated. Major League Soccer's roster rules for the 2013 season state that only the first 20 players on a roster count against the $2.95 million salary cap.

The remaining 10 players are considered "off-budget."

In addition, teams are allowed to leave roster spots 19 and 20 open, and still have 10 players on the "off-budget" part of the roster.

MLS' roster rules then list the following further classifications of groups of players:

- Players in places 1 through 24 have salaries of at least $46,500 this year
- Players in places 25-30 have salaries of at least $35,125 this year. 
- Generation Adidas players are off-budget.
- Homegrown players are off-budget.

If you're confused, well, you surely aren't alone. I've been covering MLS for over a decade and I still can't figure this stuff out much of the time.

This much I do know. Last year's roster rules contained a provision by which teams could leave open two roster spots in the 25-30 category and claim $35,000 in allocation money per spot. Though the 2013 roster rules have not been formally announced yet, I have seen a copy of them and that provision no longer exists.

With all of that said, I think I have a somewhat decent idea of how the Union's roster breaks down at this point. Here's my stab at the Union's groups of on-budget and off-budget players.

To be absolutely clear: this is just a guess. It is not a statement of fact.

I am hedging on it because more than anything else, it should serve as a guideline to those of you who want to get a better understanding of how MLS' roster rules work.

Here goes:

On-Budget Players (in alphabetical order)

1. Freddy Adu (Designated Player)
2. Chris Albright
3. Brian Carroll
4. Conor Casey
5. Danny Cruz
6. Keon Daniel
7. Michael Farfan
8. Gabriel Farfan
9. Raymon Gaddis
10. Antoine Hoppenot
11. Michael Lahoud
12. Sébastien Le Toux
13. Zac MacMath
14. Jack McInerney
15. Amobi Okugo
16. Jeff Parke
17. Bakary Soumaré
18. Roger Torres
19. Sheanon Williams
20. Aaron Wheeler

Off-Budget Players

1. Chase Harrison (in overall places 21-24)
2. Greg Jordan (in overall places 21-24)
3. Matt Kassel (in overall places 21-24)
4. Chris Konopka (in overall places 21-24)
5. Don Anding
6. Leo Fernandes
7. Chandler Hoffman (Generation Adidas)
8. Cristhian Hernández (Homegrown Player)
9. Jimmy McLaughlin (Homegrown Player)

As you can see, all 20 "on-budget" roster spots are currently taken. One of them is taken by Adu.

So when Hackworth said last week that the Union would have to get rid of a player in order to sign Vidal, he wasn't kidding.

It wouldn't surprise me at all if Adu is that player.