Are teams tiring down the stretch?

Our weekly dose of Major League Soccer quick takes, plotlines to watch and Power Rankings.

A couple weeks back, Free Kicks pointed out the high number of clean sheets this season. The trend continues: In the 35 league matches played during the month of August, a team failed to score 30 times. Put it another way, there were just nine times when both squads found the back of the net (amazingly, four of these fixtures came on Aug. 23). Now compare those figures with those of June (28 matches, 13 shutouts, 15 games in which both teams scored) and July (27, 15 and 15). Something's up, no? Our best guess as to why: With MLS' small roster sizes, players are exhausted and can't get up for every game. This trend is especially prevalent road teams, who were held scoreless 18 times in August (though Seattle hasn't scored at home in three straight).

Four clubs -- FC Dallas, New York, Kansas City and the San Jose -- effectively have been eliminated from playing contention. However, the quartet still has a role to play in the MLS playoff picture. With the remaining 11 teams fighting to make the postseason, dropping points to one of these four could cripple any aspirations. Case in point: Dane Richards and the Red Bulls, who put a hurt on Columbus' attempt to run away with the No. 1 seed in the Eastern Conference. Each of the non-contenders play at least four matches against a potential playoff outfit, meaning the road to the postseason goes through MLS' worst teams.

The U.S. Open Cup concludes on Wednesday night with either the Sounders or the home side (and reigning champion) D.C. United emerging victorious at RFK Stadium (7:30 p.m. ET, Fox Soccer Channel). Elsewhere, the footballing world turns its focus to the international stage and, once again, MLS teams will suffer as their best players join their respective national teams. Fortunately for the league, only six sides -- Colorado, D.C., FC Dallas, Kansas City, New England and Toronto FC -- have matches during the week, so quality shouldn't suffer too much. The Rapids, fresh off a huge win against Houston, defend their turf as TFC comes to the Mile High City, while the Revs look to continue their assault up the league table at home against the Wizards. Finally, in a match where Tom Soehn's side needs to take all three points, FC Dallas plays host to United.