After a 16-year career that included 12 Pro Bowl selections, Junior Seau will announce his retirement today.The addition of Seau to the ranks of NFL stars who played their last game in 2005 could give the Pro Football Hall of Fame its all-time best induction class five years from now.

Seau, a linebacker who played high school ball in Oceanside, Calif., and college ball at USC, spent his first 13 seasons with the San Diego Chargers, leading the team in tackles every year and earning a reputation as one of the league’s most athletic and hardest-hitting linebackers. San Diego fans loved his toughness, his teammates respected his leadership, and in 1994 he won the league’s Man of the Year award for his community service activities.The Hall of Fame’s selection committee chose him to the league’s all-decade team for the 1990s, and he is generally regarded as the best defensive player in Chargers history.

Thinking he had reached the end of his career, the Chargers traded Seau to Miami in 2003. He hung around for three seasons as a Dolphin, but a series of injuries forced him to miss more than half of the team’s games the last two years, and to Chargers fans who idolized Seau as a hometown hero, seeing him in Miami felt like Willie Mays in a Mets uniform. Tomorrow Seau will return home to make his announcement at the Chargers’ team headquarters.

By retiring after the 2005 season, Seau will become eligible for the Hall of Fame in 2011.Other names on the Hall of Fame ballot that year will include offensive tackle Willie Roaf, who retired just before the Kansas City Chiefs opened training camp, running back Jerome Bettis, who retired from the Pittsburgh Steelers after they won the Super Bowl in February, and defensive back Deion Sanders, who announced during the 2005 season that it would be his last.

Roaf made 11 Pro Bowls, seven with the New Orleans Saints and four with the Chiefs. He came from a relatively small school, Louisiana Tech, but the Saints coveted him so much that they traded an All-Pro linebacker, Pat Swilling, to acquire the eighth overall pick and select Roaf in the 1993 draft. Roaf started at left tackle and immediately became one of football’s best linemen, both for his pass protection and for his run blocking. He made the league’s alldecade team for the 1990s and has made five Pro Bowls since then.

Bettis rarely made spectacular, highlight-reel runs – even in his best season, when he gained 1,665 yards in 1997, his longest run was just 34 yards. But he could devastate opposing defenses in short-yardage situations. He won the league’s rookie of the year award with the Los Angeles Rams in 1993, but after three years the Rams traded him to the Pittsburgh Steelers, where he had his greatest success. He finished his career with 13,662 yards, fifth best in NFL history. His best days were behind him by the time he retired, but the lasting image of returning to his home town of Detroit and winning a Super Bowl will almost certainly put him in the Hall of Fame.

The Atlanta Falcons chose Sanders, an All-American at Florida State, with the fifth overall pick in the 1989 draft. He played five years there before leaving for San Francisco as a free agent and helping the 49ers win the Super Bowl in 1994. A year later, he moved on to the Dallas Cowboys and again won a Super Bowl. After five years in Dallas he joined the Washington Redskins for the 2000 season, then retired, only to come back three years later and play for two final seasons with the Baltimore Ravens. Sanders’s antics — wearing flashy jewelry and dancing in the end zone every time he scored — sometimes obscured his dominance on defense. At his best, he could take on the opposing team’s top receiver and effectively remove him from the game. He made the 1990s all-decade team as both a cornerback and a punt returner.

Seau, Roaf, Bettis, and Sanders have a chance to make history in five years. The Hall of Fame’s selection committee, made up of 39 sportswriters, sees induction on the first ballot as a distinct honor and typically forces all but the very best players to wait a few years before earning a bust in Canton, Ohio. A few classes have included three players on their first year of eligibility, but four would be unprecedented.

But even at a record four, the list of 2011 first-ballot inductees might not be complete. Three running backs — the Jets’ Curtis Martin, the St. Louis Rams’ Marshall Faulk, and the Kansas City Chiefs’ Priest Holmes — are currently unable to play because of injuries and considering walking away for good. If all three injured running backs retire, at least one great player will fail to make the Hall of Fame in 2011 because by rule, the Hall of Fame can induct no more than six players in any year.

Holmes, whose yardage totals put him behind Martin, Bettis, and Faulk, would most likely miss the cut. For him, returning to play one last season with the Chiefs could help his chances of getting in the Hall of Fame, not because he’ll improve his career numbers (he wouldn’t get much playing time behind starter Larry Johnson) but because he would avoid having such stiff competition on the ballot in his first year of eligibility.

If Roaf, Sanders, Martin, Bettis and Faulk join Seau in the Hall of Fame in five years, the Canton class will represent a combined 49 Pro Bowls. Seau, with his 12 selections, stands above them all, meaning he could become the most accomplished player in the best Hall of Fame class ever.

Mr. Smith is a contributing editor for FootballOutsiders.com.