It’s been one of the frustrating things in watching the Seahawks over the past two games. First and 10, and the Seahawks run an outside zone play left, with Julius Jones being forced out of bounds for a 1-yard gain.

Now the Seahawks have a second and 9 yards to go, and the team’s chances of picking up a first down and moving the chains are lessened because of their inability to gain good yardage on first down.

Offensive coordinator Greg Knapp is keenly aware of this, and talked about it on Wednesday.

Knapp said the team wants to be at a 60 percent efficiency rate on first down, which means they want to gain four or more yards, either running or passing the ball, on first down. Seattle was 35 percent (9-of-26) on Monday against Dallas. They ran the ball on first down to start out on six out of the first seven drives on first down, gaining a total of three yards.

The reasoning behind establishing a good efficiency rating on first down is it makes it easier to convert on third downs.

“Greg Knapp uses the phrase ‘stay on schedule,’” Seattle quarterback Matt Hasselbeck said. “Not having negative plays. Like in the Arizona game, as an example, we had a lot of plays for negative yardage. And those are drive killers.”

Seattle’s third down conversation percentage has suffered the last two games because of the team’s struggles on first down. Against Arizona they were 0-for-11. Against Dallas they were 6-of-14 on third downs. For the season the Seahawks are at a 37 percent conversion rate on third downs, ranked 20th overall. Indianapolis leads the league with a 51 percent conversion rate on third downs. Last season Seattle was at 31 percent on third down conversions, third-worst in the league.

For the Dallas game, Seattle ran the ball 14 times on first down and threw the ball 12 times on first down, but that statistic is skewed because Seattle was behind and had to throw in the second half.

“That’s something that we have to improve on, both in the run and the pass game,” Knapp said. “It will start with the development of the line staying together and the consistency there. That will help with both the run and pass game for us. And that will help us get better in those situations. But it was a big improvement from a week ago.”

The week before, against Arizona, Seattle finished at 28 percent (5 for 18) according to Knapp’s efficiency rating system. Three of the first seven plays on first down were runs.

For comparison’s sake, Seattle was 16-of-31 on first down against Jacksonville (41-0 win) for a 52 percent efficiency rating. Seattle ran the ball 21 times on first down and passed the ball 10 times on first down, including three touchdown passes on first down.

Here are the numbers in the rest of Seattle’s games: Indianapolis (7-of-26), Chicago (11-of-28), San Francisco (13-of-29) and St. Louis (21-of-32).

Compiling all of those numbers together, Seattle has a 44 percent efficiency rate on first down (83-of-190).

As far as run/pass ratio on first down, Seattle has 91 rushing plays (3.48 average yards per rush) and 107 passing plays (6.32 average yards per passing play). Last season, the Seahawks ran 187 rushing plays (4.08 average yards per rush) and 215 passing plays (5.76 average yards per passing play).

Looking at the numbers, you would think Seattle should throw more on first down because of the chance to gain more yardage. However, while throwing the ball provides more reward, there’s also more risk involved, in terms of turning the ball over, either by a tipped ball or interception, a sack and forced fumble, or by turning the ball over by fumbling once it’s completed, or an incomplete pass, which leaves you with second-and-10.

So the coaching staff has to weigh all of those factors, along with game planning against the defense they are facing each week and making sure they know what Seattle’s tendencies are in terms of what plays they’ve ran in the past on first down.