GLENDALE, Ariz. (AP) David Johnson needed a couple of plays to realize that life as an NFL running back is a lot different than it was at Northern Iowa.
Then he did just fine.
Johnson had 66 yards rushing on 13 carries in his NFL debut, San Diego had six first-half sacks, and rookie Josh Lambo kicked a 42-yard field goal as the game ended to give the Chargers a 22-19 preseason victory over the Cardinals on Saturday night.
Johnson, a third-round pick who had been out most of training camp with a hamstring injury, also caught two passes for 15 yards.
''I thought after he quit dancing and he got out of the dance studio, he ran real well,'' Arizona coach Bruce Arians said.
Johnson said Arians told him ''get north and south. Don't dance. This isn't college anymore.''
''As the game started progressing I felt a little bit better,'' Johnson said. ''It started slowing down a little bit more. I started reading the holes a little bit more, and just helping out the offense.''
Melvin Ingram had two sacks for the Chargers.
''I felt good,'' he said. ''It's rough when you go through practice and you just tag off, but then when you finally get into a game and get a couple sacks, it's a good feeling.''
Carson Palmer, playing less than one quarter, completed a 57-yard pass to rookie speedster J.J. Nelson.
''When I let it go I thought I'd overthrown him,'' Palmer said. ''I can't wait to watch it on film. He must have hit the nitrous button because he took off and got out underneath that thing.''
The big play set up Palmer's 17-yard TD pass to John Brown.
San Diego quarterback Philip Rivers sat out the game. Kellen Clemens, starting in his place, was 9 of 15 for 88 yards.
Rookie quarterback Phillip Sims directed the Cardinals to 10 fourth-quarter points to tie it at 19 before Lambo won it.
Arizona backup Drew Stanton was sacked four times and Palmer twice.
''The defensive backs love it,'' San Diego coach Mike McCoy said. ''The more pressure you get on the quarterback, it energizes the football team, especially the big sack.''
The Chargers' lone first-half touchdown came after linebacker Kavell Conner intercepted Stanton's underthrown pass and returned it 29 yards to the Cardinals 12-yard line, leading to Branden Oliver's 3-yard scoring run.
Palmer went 3 of 7 for 88 yards and a touchdown and had a couple of passes dropped. The 35-year-old quarterback, coming back from ACL surgery, had gone 4 for 4 for 77 yards in his lone series against Kansas City the previous week.
Arizona led 6-0 when the first unit left the game after one quarter.
Lambo, kicking because Nick Novak experienced muscle tightness, made a 53-yard field goal as the half ended to tie the score 9-9 and added a 43-yarder before his winner.
''I'm just trying to take advantage of my opportunities,'' the ex-Texas A&M kicker said.
Arizona's Chandler Catanzaro had field goals of 28 and 37 yards, but missed from 38.
Each team botched an extra point from the new, longer distance. Arizona didn't even get its attempt off because holder Dave Zastudil couldn't handle the snap. After San Diego's first TD, Novak's attempt bounced off the right upright.
OFFICIALLY TICKED OFF
Arians was hoarse after the game and he blamed the officiating.
''This crew might need eight preseason games to get ready,'' he said.
McCoy said the plan all along had been for Rivers to sit this one out. Rookie running back Melvin Gordon also didn't play, still nursing a sore ankle. In San Diego's preseason opening win over Dallas, Rivers was 2-for-2 for 20 yards.
Four Charger cornerbacks also did not play: Jason Verrett, Chris Davis, Steve Williams and Greg Ducre.
Newly signed Arizona running back Chris Johnson had planned to play but came up a bit lame late in Thursday's practice.
Logan Thomas, trying to hold on to Arizona's No. 3 quarterback job, didn't complete a pass in his four attempts. Sims, who was not drafted, was 8 of 13 for 89 yards.
Chargers third-string quarterback Brad Sorensen was 13 of 22 for 122 yards and was intercepted once.
The Chargers lost wide receiver Dontrelle Inman to a concussion in the first half. Arizona wide receiver/kick returner Brittan Golden took a fierce hit from safety Adrian Phillips, stayed down for a moment before walking off the field with trainers. He returned to the game.
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