"He was our starter for a reason," Lynn said. "I like the way Austin [Ekeler] and JJ [Justin Jackson] have been working. They've done an excellent job and proved they can play in this league. They will still have a major role in this offense, but as soon as Melvin's ready, he'll go back to being our No. 1 guy."
Gordon ended his 64-day holdout due to a contract impasse with the team on Thursday. Lynn said Gordon passed a physical and was cleared to practice, and Gordon worked out on the field for the first time this season.
The Chargers (1-2) received a two-week roster exemption for the Pro Bowl running back, according to Lynn, which means he can return to the active roster as late as Week 6, when the Chargers are getting ready to face the Pittsburgh Steelers in Los Angeles.
Lynn said Gordon is unlikely to play on Sunday against the Miami Dolphins, although he could travel with the team.
Gordon arrived early on a dreary Thursday morning in Southern California. He expects 2019 will be his final season with the Chargers, a source told ESPN's Josina Anderson.
Ekeler, who has served as the team's starter with Gordon out, welcomed his teammate back to the fold with open arms.
"We've got a little swag back in the room," Ekeler said. "It's good to see Melvin back in the office. We've got one of our playmakers back on our team. I'm glad they got everything figured out and he's back with us."
Chargers offensive guard Michael Schofield III said the addition of Gordon, along with Ekeler and Jackson, should give the Chargers a strong running game.
The Chargers are No. 13 in the NFL in rushing through the first three games without Gordon, averaging 112 yards per contest. Ekeler has 160 rushing yards and four total touchdowns.
"It's exciting to have Melvin back," Schofield said. "With the way JJ and Ekeler are playing, now we have three solid backs, so that's only going to open our offense more and obviously it's going to keep them all healthy.
"He's one of the best backs in the league for sure. JJ's a little more shifty; Ekeler's more of a speed guy and he can run you over. But Melvin's kind of got it all."
Gordon desired a contract extension that would put him among the league's top-paid running backs, such as Ezekiel Elliott, Todd Gurley II, David Johnson and Le'Veon Bell. The Chargers had offered Gordon a contract that would have doubled his salary to roughly $10 million annually.
Gordon and his representation also have to resolve how they will handle the fines that have piled up during his absence.
According to the league's collective bargaining agreement, as a player on his fifth-year option of his rookie deal, Gordon can be fined $30,000 per day for missing training camp, along with one week's regular-season salary for each preseason game missed -- a total of about $2.22 million. He also can lose $989,118 worth of base salary for missing three regular-season games. He can still earn $4,615,882 if he reports and plays on his contract.
The team will seek to collect the fines, a source told ESPN.