The Chivas example is extreme. The team finished last in the Western Conference last season, then replaced coach Martin Vasquez with former US national team defender Robin Fraser, who had no previous head coaching experience. There was no reason to believe Fraser could quickly turn around a team that had lost six of its last seven games the previous season. But, nearly a third of the way through the season, Chivas (3-3-3) appears capable of being in the thick of the playoff race.

But that describes the situation of most Major League Soccer teams.

In the Western Conference, three teams have five victories, two have won four times. Five Eastern Conference teams are within 3 points of first-place New York (4-2-3, 15 points).

After falling behind competitors rejuvenated with fresh investments in star players and soccer-specific stadia, the Revolution hit a scoring slump, scoring one goal in the last three games. But a victory over Vancouver Saturday vaulted them into a three-way tie for third place with 13 points.

“We say it every year, but the parity in our league is unlike, possibly, any in the world,’’ Revolution vice president of player personnel Michael Burns said yesterday. “From game to game, whether you are playing home or on the road, games are impossible to predict. If you win two or three games you can be in a real good position and if you lose two or three games you can be in the real bad position.

“I think travel is a real issue in our league. Until Chivas’s win [Sunday night] not one team had gone cross-country in either direction and taken 3 points. And that is going to take a toll on players even more in the summer months. Expansion is a positive but, due to the size of the country and Canada, there is a significant amount of air miles and that is taxing on players.’’

Burns and Fraser competed against each other as players in the early days of MLS and were national team teammates. They symbolize MLS players transitioning to management.

Fraser worked as an assistant to Jason Kreis at Real Salt Lake, and his quick turnaround of Chivas USA is similar to a path Kreis took.

“Some people looked at Chivas in the first couple weeks as a bad team but I never thought they were as poor as they seemed to be right out of the gate,’’ Burns said. “It’s a fine line between winning a couple and losing a couple. A couple key injuries and it’s difficult to keep going. We’re all looking to add depth and quality, but a couple key injuries and it’s difficult to keep it going.’’

The MLS standard-bearers are the Los Angeles Galaxy and the Red Bulls, with by far the highest payrolls, the most high-profile performers, and, clearly, the most ambition. But LA and New York are going to be challenged by more frugal organizations.

Among the factors leveling the field are the roster limits set by the league. Season-ending injuries to Branko Boskovic (D.C. United), David Ferreira (FC Dallas), Javier Morales (Real Salt Lake), and Steve Zakuani (Seattle) have raised questions about out-of-control style of play which places attacking players at risk.

“You don’t like to see it happen but it does happen,’’ Burns said. “There have been a couple of real bad injuries the past few weeks, but I can’t remember it happening a lot the past few years. It’s not becoming the norm. The league has taken a harsh stance but nobody thinks this is becoming a trend.’’

Before recent expansion moves, the MLS regular season often seemed devalued because most teams qualified for the playoffs. Now, with 18 teams, the competitive stakes have been raised. The race to advance to postseason play likely will go to the wire for several teams.

Less than a week ago, Philadelphia seemed poised to overtake the Red Bulls. But then the Union was held to a 1-1 tie by the Galaxy at home as Colombian goalkeeper Faryd Mondragon limped through the final minutes with a groin injury. Coach Peter Nowak missed that match to compete in a charity game in Poland, raising questions about why he was allowed to skip his team’s game. Nowak returned for the Union’s 2-0 loss at FC Dallas, raising questions about what purpose he served in returning.

Last month, both Chivas USA and the Union turned down US national team midfielder Benny Feilhaber, who signed with MLS after five seasons in Europe. That left the door open for the Revolution, who immediately claimed Feilhaber. At the time, New England had one win in its first six games. Feilhaber sparked the Revolution to their second multiple-goal game of the season (a 3-2 win over Sporting Kansas City), then earned a penalty kick in the Vancouver match.

If Feilhaber had not done his part, the Revolution might well be in the midst of an eight-game winless streak. Instead, they could be a playoff contender, though they might need a couple more high-level additions.

But Burns does not expect a signing before the middle of July. The Revolution have been scouting in Europe and have committed to signing a designated player.

“We can’t do anything until the signing period opens July 15,’’ Burns said. “And [we] are not at the level of discussion to where we have made an offer to anyone in a pre-contact situation.’’

Honor for Lilly Mayor Thomas Menino has declared Friday Kristine Lilly Day in Boston; she will be honored for her historic contribution to soccer at an event at City Hall Plaza at 2 p.m. Lilly was a member of the US national team that won the 1999 World Cup, and as captain of the Breakers helped establish the women’s pro game . . . Boskovic will be sidelined for about six months following surgery to repair a torn anterior cruciate ligament in his left knee. The 30-year-old Montenegrin was injured during a US Open Cup qualifier against the Revolution April 26 . . . Diego Maradona has been hired to coach the United Arab Emirates club Al Wasl, marking the 50-year-old Argentine great’s return to coaching since leading his country to the World Cup quarterfinals last year. He signed a two-year contract; Al Wasl officials would not disclose financial terms of the deal.

Frank Dell’Apa can be reached at f_dellapa@globe.com; material from the Associated Press was used in this report.