With the Bryan brothers gone, who will dominate doubles at the Davis Cup?

If fans of U.S. Davis Cup tennis were curious about what life might be like after the Bryan brothers, they couldn't have asked for better test than the one the American squad will face this week in Birmingham, Alabama.

"It is different to not have Bob and Mike [Bryan] here," U.S. Davis Cup captain Jim Courier said in the team's pre-draw news conference on Tuesday. "I wouldn't say it's better, but I would say that we feel comfortable that we have great options at our disposal for all of the matches."

Bob and Mike Bryan, the brilliant doubles squad that anchored the U.S. Davis Cup effort for 13 years, last month announced their retirement from the competition. They would no longer be the closest thing to money in those pivotal third-rubber doubles matches on Saturday -- the only day in pro tennis that is devoted solely to doubles. The one day during which doubles alone matters -- and often matters hugely.

It's one of the unique things about Davis Cup, and one of the elements many would hate to see sacrificed.

There are three possible scenarios on any given Davis Cup Saturday, and doubles plays on an outsized role in two of them. When a team is up 2-0 in the best-of-five competition, the doubles doesn't loom so large. But at 1-1, it appears critical, and certainly at 0-2, it is all-important. Doubles contains intense pressure more often than any single singles match, and the Bryans almost always measured up.

The Bryans are the fifth-winningest Davis Cup team ever, at 24-5, with a remarkable 13-0 record on the road. They clinched the winning point -- and the Cup -- in 2007. They've also won 16 Grand Slam doubles titles.

Eight years ago, the Bryans provided the pivotal win in a tie under nearly identical circumstances in the same football-mad city against a comparable Swiss "B" team lacking the services of Roger Federer. They eked out a tension-filled four-set win over the competent Swiss doubles team of Yves Allegro and Stan Wawrinka.

That points toward another important aspect of Davis Cup doubles: Most nations can field a respectable team, even the ones that lack a threatening pair of singles players. Take India: It rarely has even one top 50 singles player, but the doubles team of Mahesh Bhupathi and Leander Paes ranks a tick higher than the Bryans in the record books. Poland and Israel also have formidable doubles teams. The detail makes the doubles success of the Bryans that much more impressive.

This Swiss team appears even weaker than that 2009 edition, which was led by No. 1 singles player Wawrinka. But that was well before Wawrinka developed into a three-time Grand Slam winner and cracked the world top three. The U.S. had a strong squad in 2009, led by Andy Roddick, James Blake and the Bryans.

The U.S. is lucky that Wawrinka and Federer both decided to skip this tie, leaving No. 127 Henri Laaksonen the top Swiss. At 35 years old, Marco Chiudinelli is ranked slightly lower, but he has a lot experience. The rankings of the other two Swiss, Adrien Bossel and Antoine Bellier, could be mistaken for gym locker combinations.

This time around, the U.S. squad consists of ATP No. 20 Jack Sock, No. 23 John Isner, No. 27 Sam Querrey and No. 31 Steve Johnson. The U.S. loses a lot without the Bryans in yoke, but it did regain an important tool when it no longer had to pencil in two of the four slots on the team to a dedicated doubles-only team: the ability to juggle the line-up. As Swiss captain Severin Luthi put it to reporters: "I don't think that it's a big advantage [for us] because they have more flexibility [without a dedicated doubles team] for singles also. When they had the brothers in the team, you knew which players are going to play singles. Now, I think all four players can also play doubles. They can change. They can wait and see how the matches on Friday went [and change the line-up]."

One of the greater advantages to this four-man US team is that the fatigue factor could be significantly mitigated. With the relaxed substitution rules, a player's freshness, or lack thereof, could trigger last-minute changes that were not tenable when the Bryans comprised half the squad.

"We were blessed to have Bob and Mike on our team for so many years," Courier said. "They're incredible. We'll miss them for sure. [But] I have a lot of confidence in these guys. Any combination of these four players would be a very, very good doubles team."

The most formidable U.S. doubles team on paper would be Sock and Isner. Sock will play first singles, but he's probably also the best doubles player in the group. He won Wimbledon doubles with Canada's Vasek Pospisil and two Masters 1000 titles, one of them with Isner. But Isner also won a Masters 1000 with Querrey.

The U.S. captain, denied options for so long, now has almost too many to keep everyone content. He's stuck between a pillow and a soft place.

Said Luthi of the U.S. players: "They're not like doubles specialists, but we know they already had great results also in doubles. They are a very strong team."