Gates agreed to a five-year, $36.175 million contract extension with the Chargers, with $20.4 million guaranteed, a league source told NFL Network insider Jason La Canfora. The deal averages $7.235 million per season from 2011 to 2015.
Gates, a college basketball star at Kent State, blossomed from a rookie free agent in 2003 to a superstar who is a three-time All-Pro and six-time Pro Bowl pick.
Three other Chargers players are unhappy about their contracts, but talks with Gates apparently intensified this week. Gates and other veterans are scheduled to report to training camp Thursday, with the first full-squad practice Friday.
"I've been blessed my whole career to be with one team," Gates said in a statement released by the team. "It's always good to get it out of the way. The goal is to win a championship. We all are human and it becomes a distraction even though you might not want it to be. It's always great to be able to go ahead and do what you need to do and get it out of the way."
It wasn't clear if Gates' deal would lead to new contracts for restricted free agents Marcus McNeill, Vincent Jackson and Shawne Merriman.
McNeill, the left tackle who protects quarterback Philip Rivers' blind side, and Jackson, a Pro Bowl wide receiver with back-to-back 1,000-yard seasons, are unhappy that they haven't been given long-term deals and are expected to hold out through training camp and the season's first 10 games. They are expected to return for the final six games to accrue another season toward unrestricted free agency.
Jackson and McNeill were tendered one-year deals at just more than $3 million each. When they didn't sign the offers by June 15, the Chargers were entitled to offer them their same salaries as 2009, resulting in a loss of about $2.5 million each.
Merriman hasn't signed his tender for $3.269 million, but the outside linebacker was due a 10 percent raise anyway, which would put his 2010 pay at approximately the tender amount. Still, he hasn't said when he'll report.
Gates held out during training camp that year, leading Chargers general manager A.J. Smith to take the extreme measure of placing the tight end on the roster exempt list in an attempt to break the impasse, automatically triggering a three-game suspension. Gates missed the final two preseason games and the season opener, which the Chargers lost.
Gates dumped the agent who represented him then and hired Tom Condon.
"Antonio is a special player and person. He is everything we are looking for in a Chargers player," Smith said in a statement. "His talent and contributions to our team speak for themselves. His work ethic and desire to be the best are unmatched. He has been a major part of the success we have had over the past several years, and we are thrilled he will continue to be with us for years to come."
Since his rookie season, Gates leads NFL tight ends in touchdown catches (59), and he ranks second in receiving yards (6,223) and third in receptions (479). Gates has led the Chargers in receptions each of the last six seasons. In 2009, he topped the team with 79 catches and a career-best 1,157 yards, with eight touchdowns.
This is the second big contract for a Chargers player in less than a year. Rivers was given a six-year contract extension worth nearly $93 million toward the end of last year's training camp.
The Associated Press contributed to this report