Quarterback Robert Griffin III has signed a contract with the Washington Redskins, the team announced Wednesday.

Quarterback Robert Griffin III makes it official. (via @redskins )

He tweeted Wednesday morning, “Well people.... It's Time to go to Work!!! off the unemployment line and oh yeah HTTR!!!!"

Griffin’s deal is worth $21.1 million over four seasons and, under the terms of the sport’s rookie pay system, contains a team option for a fifth season. The pact includes a signing bonus of $13.8 million. Griffin’s salary for the 2012 season is $390,000, the rookie minimum.

The quarterback joined other rookies at Redskins Park Wednesday. He had been absent from the facility Monday and Tuesday when other rookies gathered there for conditioning workouts and classroom work prior to next week’s opening of training camp. Redskins veterans report to camp next Wednesday and the opening practice of camp is scheduled for the following day.

Redskins officials declined to comment beyond a written release issued by the team announcing the signing, and decided not to make Griffin available for comment.

Griffin, the Heisman Trophy winner at Baylor last season, already has been named the Redskins’ starter by Coach Mike Shanahan.

The team's final unsigned rookie is guard Josh LeRibeus, a third round pick.

Under the NFL’s rookie pay system, the Redskins would have to exercise their option for a fifth year of the deal following Griffin’s third season. Because he was a top 10 draft pick, Griffin’s fifth-season salary would equal the average salary of the 10 highest-paid NFL quarterbacks.

Some in the league were surprised that Griffin signed a contract before quarterback Andrew Luck, the Stanford product drafted first overall in April by the Indianapolis Colts.

Griffin’s contract contains no “offset language,” according to one person with knowledge of the deal who spoke on condition of anonymity because all its aspects have not been made public. That provision had been a stumbling block in negotiations for many top picks.

Without the language, the Redskins would owe Griffin the full amount of his guaranteed contract if they release him and he signs with another team, regardless of his salary from the new franchise.

Griffin’s agent, Ben Dogra, confirmed the deal but declined to say whether the contract includes offset language.

“He wanted to get there and give himself the best chance to be successful for his rookie year,” Dogra said in an e-mail.