Dwayne De Rosario is the best player in Major League Soccer. He is the best player in the history of Major League Soccer. There, I said it.

What De Rosario did on Saturday night against Real Salt Lake was nothing short of jaw-dropping. His first half performance was possibly the greatest half in the regular season by one player in the history of the league. Real Salt Lake are not a bad team, and though their defending on D.C. United's first two goals could have been better, they did not play poorly.

In fact, until Andy Najar's opening goal in the 13th minute, Real Salt Lake had been the far superior team. There appeared to be a large gap between the United strikers and midfield as De Rosario played high and Kyle Beckerman was able to dictate the pace of play. RSL looked dangerous going forward when they played direct balls for Paulo Junior, Alvaro Alvarez and Jean Alexandre to run onto. They looked very much like the team that had won their last five consecutive games.

Then, lightning struck. For what seemed like the first time in the game, De Rosario dropped deep to pick up the ball around the half-way line in the 13th minute. Quickly, he turned himself around, spotted Najar running down the right, and played a perfect through ball to Najar through tons of traffic. It hit the Honduran winger perfectly in stride, and he went on to score. De Rosario's pass was incredible - Xavi-esque, even. Think that's a hyperbolic statement? Watch it again.

The second goal, a header by De Rosario from close range, had a lot to do with a spectacular cross by Najar and some poor defending by Rauwshan McKenzie, it had just as much to do with two other things that might not have been that obvious. First, Stephen King's tackle and pass to start the move. King has been a solid but unspectacular player for DC throughout his career, but he's seriously stepped up in recent weeks, and his performance against RSL was perhaps one of the two or three best of his career. Second, De Rosario's movement off the ball - both to come back to midfield, then take off on a run at goal - was perfect. It was a different class by MLS standards.

Major League Soccer has some fantastic, world class athletes and plenty of players with enough skill to make it at the highest levels of football, but the biggest difference between MLS and the big European and South American leagues for quality of play is almost certainly in the small details. It's the pitch awareness and tactical acumen that truly separates De Rosario from his peers. Even some of Major League Soccer's best attacking players - Fredy Montero, Javier Morales, David Ferreira - whether they play attacking midfield or second striker do not have the same movement off the ball.

So, that's the first two goals. Teamwork and movement off the ball, combined with some below-average defending were the key ingredients. The third and fourth goals, though? Unstoppable. Nothing but skill and power from De Rosario. Both his second goal, which came from open play, and his third, a direct free kick, were stunning. They were placed perfectly and hit with power.

The four goals that DC scored against RSL all had De Rosario as a center piece and all of them were different. The first came from his creativity and vision, the second from his tactical acumen and work rate, the third on a powerful shot from open play, and the fourth on a powerful, bending shot from a dead ball. He guided his team to an emphatic victory by using every skill one could ever want their attacking midfielder or second striker to have.

Is it reasonable to expect a performance even close to that good against the Philadelphia Union on Thursday night? No, absolutely not. As good as De Rosario is, that might have been a once in a lifetime kind of performance. Cristiano Ronaldo and Lionel Messi are perhaps the only players on the planet who have ever done anything like that twice at a reasonably high level of play. Thierry Henry and Zinedine Zidane probably had more than one game that good in their careers. Not to compare De Rosario to those legends of the game (he's obviously not THAT good), but it was an incredible rarity.

However, De Rosario's been consistently fantastic since joining the Black And Red. Before he showed up, they were a fringe playoff team at best, on the outside looking in. Despite their extremely young defense and their constant injury problems, DC is currently in the playoffs on points per game, with a couple in hand over most of their rivals. Unquestionably, he will be a key player for them against Philadelphia.

The Union are battling for a playoff spot as well, and could very easily finish on top of the Eastern Conference or out of the race, just like...well, basically the entire Eastern Conference. Is it the JV League? Yes, probably, but that doesn't mean it isn't fun and dramatic. Like it or not, the points and records mean nothing when the playoffs start. No team in the East is as good as Los Angeles, Salt Lake or Seattle, but Colorado wasn't even one of the five best teams in MLS last season. That's the beauty (or repulsiveness?) of the system.

Coming into the game, Philly has received a whole bunch of good news. Both Freddy Adu and Sheanon Williams have recovered from injuries. They're believed to be available for the starting XI, but both should be on the bench at the very least. Danny Mwanga is also close to returning from injury, and is listed as questionable. Should all three be fit to start, Philly suddenly have a team that looks a little better than DC's on paper.

Then again, RSL's team is a hell of a lot better than DC on paper, even with Javier Morales and Alvaro Saborio on the bench and Jamison Olave out injured. De Rosario can nullify almost any advantage on his day, and Philly isn't good enough that he won't have a significant influence on the game.

Way too many words later, here are five thoughts heading into this matchup.

1. Don't worry about Zac MacMath

Before coming to MLS, the Philadelphia Union goalkeeper had been in a number of pressure situations in NCAA soccer and U.S. youth international matches. Unsurprisingly, he's stepped in for the injured Faryd Mondragon and played extremely well. He doesn't look like a rookie; he's going to make a major mistake and cost his team the game. MacMath is already a high-level MLS keeper.

2. Ben Olsen is praying for a Brian Carroll-Kyle Nakazawa midfield pairing

Or, even better, either of those two players and Stefani Miglioranzi. DC United plays with two holding midfield players who don't get forward a whole lot, so it doesn't seem terribly necessary for Nowak to put in two holders of his own. But, if he does want to go that route, Amobi Okugo would be a much better option. He performed well against Kansas City last week (unlike Brian Carroll, which was surprising), and why he was ever out of favor is one of the world's great unsolved mysteries.

3. Clyde Simms vs. Sebastien Le Toux, not DC defense vs. Le Toux, is the biggest matchup in this game

If Ethan White or Brandon McDonald is stepping up to close down Sebastien Le Toux when he drops deep to receive the ball, DC have problems. This will probably happen infrequently, on account of Ben Olsen not being an idiot. Since Philly's center midfielders get forward so sparingly, Clyde Simms will be better used trying to deny service to the feet of Le Toux, rather than tracking the runs of the midfielders. If you've never had the pleasure of seeing Simms' work off the ball in this regard in person, he's really good at it.

4. Should this end in a blowout either way, the losing team doesn't need to panic

After this game, teams in the East will have anywhere between three and five games remaining, and the teams in contention are separated by six points. This race will go down to the wire. Either team could lose 5-0 tonight and still clinch an automatic playoffs spot.

5. Prepare for the Andy Najar show

Philly have enough quality all over the pitch to win this game even if Andy Najar goes crazy, but the matchup on their left, DC's right is a pretty bad one. Roger Torres and Freddy Adu aren't exactly adept at tracking back and defending, while the Farfan brothers - one of whom is likely to start at left back - are average at defending for fullbacks. Peter Nowak should consider playing Gabriel and Michael on the same flank to try and neutralize Najar. If the left flank features one of the brothers and either Adu or Torres, prepare for the young Honduran to be DC's best player - even better than De Rosario.

Projected Philadelphia Union lineup (4-4-2): MacMath; G. Farfan, Califf, Valdes, Williams; Adu, Okugo, Carroll, Torres; Le Toux, Paunovic

Projected D.C. United lineup (4-4-2): Hamid; Kitchen, McDonald, White, Burch; Quaranta, Simms, King, Najar; De Rosario, Wolff

Pick: 2-1 DC

Philadelphia Union vs. DC United kicks off at 8:00 pm ET from PPL Park in Chester, PA. The game can be seen on ESPN2 and WatchESPN.com in the USA. We'll have coverage of the game in our MLS Midweek 29 StoryStream. For more on the Black And Red, check out SB Nation's DC United blog Black And Red United. For more on the Union, check out our Philadelphia Union blog Brotherly Game.