SAN DIEGO (AP) The Chargers were determined to fix their woeful running game this offseason.

They climbed the draft board to secure standout Wisconsin running back Melvin Gordon.

They revamped their offensive line, which has just one returning starter at his same position for the season opener.

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But after three preseason games, their average rests at 3.4 yards per carry- the same as it was last season.

''We are just trying to get better as a team,'' coach Mike McCoy said after Tuesday's practice. ''There are pluses and minuses. There are plays that look really good and there are plays that have a lack of finish or lack of execution.''

The Chargers end their preseason on Thursday against the San Francisco 49ers.

McCoy said there are various reasons why the Chargers are struggling.

''Whether it's a blocking scheme, a guy not doing what he is supposed to be doing, a guy not finishing his block, whether it's a quarterback not getting us in the right play, whether it's not bringing a receiver down to block the force, there's a number of things,'' he said.

What McCoy is certain of is Gordon's skills. Even if the Heisman Trophy finalist has only 45 yards on 20 carries for a 2.3-yard average.

''Without a doubt,'' McCoy said. ''I have a ton of confidence in Melvin Gordon, a ton of confidence. He is a very good football player and has done everything we have asked. I look forward to him having a great year.''

Gordon, who isn't expected to play Thursday, has done well on some plays. But on others, he's slow to the hole or struggled in pass protection.

''I still got a lot to improve on,'' Gordon said. ''But it's everything I thought it would be. I knew it would be tough, I knew guys would be fast, I knew guys would be strong. It kind of takes me back to my freshman year of college when you are getting adjusted and acclimated to everything. Everyone is moving a lot faster than you are.''

The Chargers need to get up to speed quickly. And McCoy stressed Gordon will have help with Danny Woodhead returning from a broken leg and Branden Oliver, the Chargers' leading rusher last year, averaging nearly 4 yards a carry this summer.

''That's what training camp and the preseason games are for,'' McCoy said of finding the right mix. ''We're learning every day and trying to improve some things.''

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