ALLEN PARK, Mich. (AP) Calvin Johnson doesn't think age has slowed him down. He is looking forward to proving it to opposing defenses this season.

The nine-year veteran celebrates his 30th birthday on Sept. 25 and still thinks he can lead the NFL in yards receiving, even after battling nagging injuries much of the last two seasons.

''No doubt,'' he said Wednesday. ''I've still got it in me.''

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The opener at San Diego on Sunday will be the first time Detroit fans will see the Pro Bowl receiver this season. The coaching staff kept him out of the team's four exhibition games and coach Jim Caldwell flashed a smile when asked how effective he expected Johnson to be.

''I know this much: He's well-rested,'' the coach said.

Johnson tweaked an ankle in the Lions' third regular season game before suffering a high ankle sprain in a Week 5 loss to Buffalo. After that, he said he never felt completely healthy the rest of the season.

He missed three games and parts of two others in the middle of the season but still managed 1,077 yards - his lowest total since 2009 - and eight touchdowns on 71 catches.

Even with the star wideout hobbled for most of the year, the Lions finished 11-5 and secured an NFC wild card berth. Two big reasons were a strong defense and the emergence of free agent Golden Tate, who played all 16 regular-season games and finished with 1,331 yards and four touchdowns on 99 receptions. His performance helped energize an offense that often struggled when the 6-foot-5 Johnson didn't play or was used as a decoy.

''The way he stepped it up when I went down, he really filled the void,'' Johnson said of Tate. ''I know what I can do. As long as I'm healthy and on the field we're going to produce.''

A healthy duo should only help quarterback Matthew Stafford, who doesn't notice anything slow about his favorite receiver.

''He looks pretty good to me,'' Stafford said of Johnson. ''He's flying around, running, catching, jumping - all the stuff he's been able to do. He's the same old guy to me. Obviously he's an all-time great. It'll be a lot of fun to have him out there.''

That greatness is hard to miss. Since Johnson arrived in the 2007 season, he's caught a league-best 74 touchdowns and recorded five games with 200 or more yards. His current 87.4 yards per game average is the best in NFL history.

''I know I'm turning 30 but my body feels good now,'' he said.

His size could be an asset against the Chargers, who start cornerbacks Jason Verrett (5-10) and Brandon Flowers (5-9). Johnson also stands a full half-foot taller than any of San Diego's safeties.

Chargers coach Mike McCoy seemed resigned to working to contain Johnson and Tate.

''They're going to make their fair share of plays,'' he said. ''They're a very talented group and we're going to have to play our best game against them.''

NOTES: LBr DeAndre Levy (hip) and G Larry Warford (ankle) did not practice Wednesday. The team said TE Eric Ebron (ankle), T LaAdrian Waddle (elbow) and LB Tahir Whitehead (elbow) had limited participation in the session. Waddle, the projected starter at right tackle, said he was not certain he would play in the opener. . RB Joique Bell, who missed all of the preseason and training camp while recovering from offseason Achilles tendon and knee procedures, was in full pads with his teammates Wednesday. . The Lions won't see Detroit native Antonio Gates on Sunday. The tight end will miss the first four games of the season for violating the NFL's performance-enhancing drug policy.