(Photo by Christopher Lee/Getty Images)

After 12 years of non-stop international soccer, Tim Howard needs a break.

The 35-year-old Howard will not be  available for friendlies or next summer’s CONCACAF Gold Cup.

As Steven Goff reported:

“Howard, who made his U.S. debut in 2002, is the program’s all-time leader among goalies in appearances (104) and victories (55), and second in shutouts (34). Aside from his club career, Howard is entering his second season as a part-time analyst for NBC Sports’ coverage of the Premier League. His children Jacob and Ali are 8 and 7 years old, respectively and live with Howard’s ex-wife in Tennessee.”

So who should replace Howard in the interim? There are three leading candidates— Aston Villa’s Brad Guzan, Real Salt Lake’s Nick Rimando and D.C. United’s Bill Hamid. The 29-year-old Guzan is reportedly the  favorite to fill-in for Howard.

Here’s how the keepers compare to Howard in terms of how often they concede goals. So the higher the number, the fewer goals they concede.

By this metric, Rimando appears to be the best keeper. But the problem with quantifying goalkeepers is that one metric is rarely enough to account for all of the key variables. If the best keeper in the world played behind a porous defense, he would still allow goals due to the sheer volume of shot attempts coming his way. So part of the reason Rimando is so far ahead of Guzan and Hamid can be attributed to Real Salt Lake’s defense, which ranked second in the MLS last season, according to Squawka’s team defense ratings. Rimando, meanwhile, ranked ninth among MLS goalkeepers.

Hamid’s performance falls in line with D.C. United’s generally lackluster defense last season. United’s defense ranked 16th, while Hamid ranked 18th among goalkeepers. Guzan ranked 14th among Premier League keepers, while Villa’s defense ranked 18th.

So by this evaluation, Guzan was four ranking spots higher than his defense, while Rimando was nine spots worse.

Still not convinced? The real separation between the keepers stems from the level of competition they face on a weekly basis. By virtue of playing in the Premier League, Guzan is better equipped to face elite talent on the international stage.

At the 2014 World Cup, more footballers (130) played professionally in the Premier League than any other league in the world. By comparison, the MLS (31 players) ranked eighth.

The other deciding factor is age. Rimando is 35 and for that reason isn’t a smart long-term investment, while Hamid is just 23 and still needs to develop further before he’s ready to be a goalkeeper on the world stage. To that end, a move to Europe at some point in the next few years, would be a smart career decision for Hamid.

The 29-year-old Guzan will be the best option in four year’s time if Howard doesn’t make the next World Cup squad in 2018. Even though goalkeepers can be effective into their late 30s, Howard will be 39 by then. Only two players were 39 or older in the last World Cup. That’s not to say that Howard can’t do it, but it’s prudent for him to rest now and for the USMNT to give Guzan valuable international experience.