As the Summer Games draw near, Gregory Ruckman is fighting with the relentless tenacity of an Olympic athlete and the keen intellect of a Harvard graduate. But the two-time Olympic rower won’t be going for the gold in Beijing this year. Instead, he’s locked in a long-running battle with America’s Olympic bureaucracy over a system that he says reeks of favoritism and allows coaches to deny competitors a fair shot at making the Olympic team.

“After rowing for eight years through two Olympics, I couldn’t abide it anymore,” Mr. Ruckman told The New York Sun. “The day I came back from Athens, I took a long walk and decided, I love this sport, I want it to be part of my life, but I cannot do it if I do not make my best effort to change things.”

Now, after four years of clashing with the U.S. Rowing Association, which selects the Olympic team, and with the U.S. Olympic Committee, Mr. Ruckman has accumulated many losses, a few small victories, and a series of grievances about the way athletes who challenge the status quo are treated. However, the rower’s central complaint is that teams for four-man boats to compete at the Olympics are picked not through open trials, as they once were, but through a “selection camp” where coaches wield great influence over the makeup of the teams.

Through the 2000 games, open trials were always used for the so-called lightweight men’s four. However, in 2001, U.S. Rowing switched to the camp-based process for four-man boats in Olympic events.

“The results declined precipitously when we moved to a totally subjective, no-trials selection,” Mr. Ruckman, 34, said. “It should be on the field of play. Do best of three if you want. Fastest on the water. It’s the fair, American, meritocratic way.”

The executive director of U.S. Rowing, Glenn Merry, said the camp system is simply better for putting together large rowing teams. “On small boats, we have open trials and anybody or any pair can come and duke it out. The reason we don’t do that on large boats is we’ve seen over time that bringing all of the talent pool in one location and assembling the best talent in a team boat with the top talent is the way to win,” he said. “It’s also the way the rest of the world does it.”

Mr. Merry also rejected proposals from Mr. Ruckman and others to leave the training camp system in place, but allow outside boats to vie against the sanctioned team sometime prior to the games. “What Greg is asking is once USA Basketball assembles their dream team, he can challenge them. It’s a big distraction,” the rowing official said.

The system clearly worked well for the American eight-man boat in 2004, when it brought home the gold, but it has proved less successful for the four-man teams.

“Greg has a very legitimate claim with the lightweight four,” an American rower who competed in a heavyweight four-man boat that missed medals at the 2000 and 2004 games, Michael Wherley, said. “The U.S. has a huge stable of lightweight men’s rowers to pick from, yet our average place in the last 11 years has been like eighth.”

Mr. Wherley, 36, who is not competing for the team this year, said such a high priority is put on the eight-man team that four-man boats are often shortchanged. “You have to erase the mind-set that doing well in the eight is good enough. I’ve seen a lot of talented rowers not get used the way they could have been used because the coaches are just not able to handle all those athletes.”

Another factor that has led to calls for more objective standards is that the strong-willed head coach for men’s rowing, Michael Teti, 51, oversees a process through which his younger brother, Paul, 31, was selected for the 2000 and 2004 lightweight men’s teams.

“Then as now, safeguards are in place which include other coaches running the selection along with the head coach,” Mr. Merry said.

The younger Mr. Teti is trying out again at this year’s camp, which officially ends today. The members of the American Olympic team are set to be announced on Friday.

In the 2000 Olympics, Mr. Ruckman’s boat came in sixth in the lightweight men’s four. In 2004, with the four-man boats being selected through the camp, Mr. Ruckman switched to a two-man boat, qualified in an open trial, and came in seventh in Athens. The following year, he attended the camp, but he contends he was kicked out for advocating for an open selection process.

Mr. Ruckman said he declined to seek a spot at the selection camp this year “on principle,” though he has remained in top shape. He recently posted the best “ergometer” or machine-tested rowing score for an American portside rower in the past four years.

Since 2005, Mr. Ruckman has filed four lawsuits against U.S. Rowing and seven complaints with the U.S. Olympic Committee challenging aspects of the rowing selection procedures, the federation’s internal governance, and its procedures for allocating so-called elite athlete health insurance.

In a 1992 case not involving Mr. Ruckman, an arbitrator, Jack Friedman, ruled that the selection camp and a pre-camp, under the rules at the time, constituted “a deprivation of opportunity to qualify for the Olympic Games.” However, in March of this year, a three-man arbitration panel ruled against Mr. Ruckman’s challenge to the current selection camp process. “This evidence does not demonstrate a denial of an opportunity; it demonstrates a difference of opinion as to the best means of selection,” they wrote, though they did restore a race that could help rowers win an invitation to the camp.

Ruling on another of Mr. Ruckman’s complaints last month, another arbitrator, Edward Costello, urged the former Olympian to throw in the towel, at least in the legal arena. “One time-honored quality of an athlete is that he or she be a good loser,” Mr. Costello wrote, though he also took note of Vincent Lombardi’s aphorism “Show me a good loser and I’ll show you a loser.”

“I respectfully suggest it is time for Mr. Ruckman to select another venue for his arguments,” Mr. Costello wrote.

Mr. Ruckman’s own hopes of returning to the Olympics may be dimming, but he vows to keep fighting against what he views as opaque and arbitrary standards.

“The ends do not justify the means,” the renegade rower said. “This is America. It’s not China. It’s not the U.S.S.R. When we send Olympians, they represent our country.”