LAKE FOREST, Ill. -- Chicago Bears running back Matt Forte insists statistics aren’t important but admits to feeling “frustrated” about the team’s inability thus far to run the ball effectively.

After averaging 4.8 yards per attempt on an 82-yard day in the season opener against Buffalo, Forte has rushed for a total of 54 yards the last two games with an average of 2.2 yards per carry.

“It is frustrating during the game,” Forte said. “It’s not that we’re not calling runs. We are calling run plays. But sometimes, the defenses are set up so that the run play we call is not going to work against that defense. Each week we’re continuing to work on it, and we’ve got to get everybody on the same page up front. Some guys that are stepping in for injured players, we have to get everybody on the right page where we’re blocking the right looks so if they change the personnel or change to a different defensive front, we know how to block that as well.”

Starting center Roberto Garza and left guard Matt Slauson suffered high ankle sprains in Week 1 and haven’t played since. Veteran Brian de la Puente and rookie Michael Ola have filled in at those spots, somewhat throwing off the chemistry and precise timing between the offensive line and Forte.

Forte said the fill-ins along the offensive line haven’t affected play-calling.

“It’s just sometimes we might have blocked it wrong or didn’t block somebody or whatever the problem was,” Forte said. “There is a little bit of a learning curve when we’re so used to having Slauson and Garza in there, and those five [offensive linemen] solidify that line. There is a little bit of a learning curve, but that’s with every team in the league. Everybody has injuries, and everybody has to step up. We have to figure that out and make it work.”

It’s certainly possible, especially facing a 30th-ranked Packers rush defense on Sunday that is allowing an average of 156.3 rushing yards per game.

“Last year when we played them, [Clay] Matthews didn’t play and that makes a big difference when he’s in the game,” Bears offensive coordinator Aaron Kromer said. “They’re at full strength now. So we need to bring our 'A' game to gain yards and have Matt Forte gain yards. We need to continue to work a balanced attack and give him opportunities.”

Bears coach Marc Trestman downplayed the significance of de la Puente and Ola stepping into the starting lineup. After all, de la Puente came into the season having started 44 games with the New Orleans Saints, who run a system very similar to Chicago’s. Ola, meanwhile, is a rookie.

But the truth is that each of Chicago’s first three opponents -- Buffalo, San Francisco and the New York Jets -- currently rank in the top 10 in the NFL in rush defense.

“Everybody’s gonna have an opinion on that,” Trestman explained. “We’ve had two very difficult weeks against two extremely strong fronts. That doesn’t mean we’re making excuses for it. We recognize we’ve got to get better. We had a reasonable start in Game 1. We’ve been bogged down the last couple weeks. We’re cognizant of that. We’re making it a point of emphasis. But we think we’ve got to work through the next few games and try to get a sense for where we really are with things. I can tell you we’re working at it.

“The fact of the matter is Brian de la Puente has played a lot of football. Michael Ola hasn’t, but I don’t think having two new guys in there has taken away from our ability to run the football. I think it goes a lot deeper than that.”