A soccer player's 30th birthday isn't usually a cause for celebration. In a sport where teenagers can make a major impact and fitness is king, crossing the threshold from the 20s to the 30s often signals the beginning of the end for many players.

That is simply not the case for goalkeepers, a position where old age isn't a limitation. Experience is king for goalkeepers, and it simply doesn't happen overnight.

There's evidence of this around the world, but particularly here in Major League Soccer. The top three keepers in the league in terms of goals against average are in their mid-30s and beyond, with Houston's Pat Onstad leading the way at age 40.

Checking in at No. 4 is Real Salt Lake keeper Nick Rimando, who celebrated his 30th birthday on June 17 and is in the midst of a career year.

"Everybody says you mature and you get better as you get older as a goalkeeper, and I think that's something that's sinking in in the last couple of years," said Rimando. "I'm a little more patient and doing the simple things right, and this year is one of those years the ball seems a little bit bigger."

The result is a 0.97 goals against average, four shutouts and a 5-4-3 record.

Onstad leads MLS with a 0.67 average, followed by Chivas' Zach Thornton, 35, at 0.80 and Seattle's Kasey Keller, 39, at 0.84.

Rimando's career-best goals against average is 1.00, which he achieved in 13 games in 2004 in leading D.C. United to the MLS Cup. Half of the 2009 season remains for his 0.97 average to potentially rise, but with Rimando seeing things so clearly there's a better chance it will fall in the second half of the season.

"He's one of the most solid goalkeepers in the league," said RSL assistant coach Jeff Cassar. "Athletically he's just as gifted as he was when he was 18. What's going on now is his angle play, his distribution and game management is at another level. I think the team feels very comfortable and very at ease when he's back there."

Collectively, RSL's team defense is better than it's ever been and Rimando has only saved 27 shots in 12 games this year, a pace that should put him well below the 96 shots he saved in 30 games last year. Both seasons pale in comparison to the 146 saves he made during his first season with RSL in 2006, an equally impressive season in its own right considering he finished with seven shutouts.

"Experience plays a big role in being a good goalkeeper. I've played against certain players for a while, and being comfortable with our backs and our system here I think that has a big role with us doing so well in the back," said Rimando.