"I had an opportunity to give Dontrelle a chance and he did the rest," said Clemens, the new backup quarterback for San Diego. "He had a great release and then got past him. Once he got it, turned the jets on and pulled away. It was fun to watch."
Inman, who played the last two seasons in the CFL, said it was "kind of stressful" with so much open field ahead. "First you want for the ball to come down and then you actually have to run another 50 or 40 yards. It's very stressful."
Clemens signed as a free agent in March to serve as backup to Philip Rivers after Charlie Whitehurst left for Tennessee. Clemens spent the last two seasons with the St. Louis Rams as a backup to starter Sam Bradford. He started the last nine games after Bradford went down with a knee injury.
Rivers played just the opening series, completing all four passes for 61 yards.
That drive ended when Ryan Mathews, who has a history of fumbling, lost the ball as he tried to go over the pile and into the end zone. Dallas' Terrance Mitchell recovered in the end zone for a touchback.
Brandon Weeden, making his Cowboys debut, finished the ensuing drive by weathering a big hit and completing a 4-yard scoring pass to James Hanna, who pulled it in while falling to the ground in the back of the end zone. Chargers defensive end Lawrence Guy injured a shoulder hitting Weeden.
"I must be a lot bigger than I think," Weeden said.
"I had to keep it alive. They covered the flat with the first read and Hanna did a great job of stopping. I had to get out of the pocket because that protection is not going to hold up forever. There was a huge hole and I knew it was going to close up quick so I threw it as hard as I could and got off the ground. When you get off the ground that is when they have a chance to pile drive you and he got me pretty good.
"It never hurts as bad when you complete them and it dang sure don't hurt as bad when you get a touchdown."
With Tony Romo sitting out to rest his surgically repaired back, Weeden started and played the first half. He completed 13 of 17 passes for 107 yards. He signed with Dallas after spending two seasons with Cleveland.
Caleb Hanie took over for Weeden on the Cowboys' first drive of the second half.
Undrafted rookie Branden Oliver scored on a 16-yard run for San Diego in the second quarter.
Inman had three catches for 107 yards. ... San Diego rushed for 152 yards. Oliver had 64 yards on seven carries and Marion Grice had 35 yards on 14 carries. ... Dallas' Joseph Randle carried 13 times for 50 yards.
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