IRVING — Dallas Cowboys quarterback Tony Romo has spent the past two games being used as a piñata by opposing defensive linemen and watching his favorite receiver, tight end Jason Witten, let a season’s worth of passes slip through his fingers.

Although there has been no public grumbling from Romo, teammates understand the frustration that is building within their offensive leader as the Cowboys (2-1) prepare to face Chicago (2-1), the team that leads the NFL in sacks (14), in Monday’s game at Cowboys Stadium.

“We’ve been around Tony long enough that we can tell, based on his facial expressions, how he’s feeling. He shows his emotions to us,” said offensive guard Nate Livings. “So he doesn’t have to say anything. We see what he’s going through.”

That included four sacks and multiple knockdowns, triggering two lost fumbles in pass-rush situations, in last week’s 16-10 victory over Tampa Bay. It has included an NFL-high five dropped passes this season by Witten, a seven-time Pro Bowler whose season average for drops had been three per year over the past four seasons (2008-2011), based on data collected by STATS, Inc.

“I’m sure he’s wondering what’s wrong,” Witten said of his uncharacteristic drops of Romo passes. “At the end of the day, those are big plays for him, big plays for our offense. You don’t just get built in to get those throws … next time because of what number is on the back of the jersey. It’s a show-me game.”

And Romo, for now, is showing remarkable patience while maintaining a positive outlook about a Dallas offense that is tied for last among NFL teams in scoring average (15.6 per game). The Cowboys’ 47 points marks the fewest in a three-game stretch by a Romo-led offense since 2009.

Despite Romo’s 89.3 passer rating and 64.8 completion rate, the offense regularly plays from behind the chains because of 12 false-start penalties in three games. But Romo said Friday that his confidence level working behind the team’s rebuilt offensive line remains high — he gave it a “10” on a 1-10 scale — and that frustration, from his perspective, has yet to surface.

“No,” Romo said. “It’s about winning and losing. You want to execute to the highest level each week. But at the same time, [winning and losing] is what it comes down to. All the other stuff is just about getting better.”

From an offensive standpoint, Romo acknowledged the Cowboys “need to do the little things better” if they are to build on their 2-1 start. Toward that end, he has addressed the offense’s shortcomings, particularly the pre-snap penalties, in discussions with teammates.

“You’re always letting the team know what you need to do to be successful,” Romo said. “And me being in a leadership role, that obviously needs to be addressed.

“We need to do the little things better. That will help us a lot because we’re already doing enough good things. We just need to minimize the stuff that you can control. The stuff that should be stuff that we’re good at.”

At the top of the list, Romo cited penalties and negative-yardage runs. So did offensive line coach Bill Callahan, who said shortcomings in those areas against Tampa Bay put the offense in too many obvious passing situations that led to too many “hellacious hits” on Romo, who is 32.

“We have to do a better job keeping Tony clean,” Callahan said.

Romo, who was sacked a career-high 36 times last season, downplayed any concerns about residual hits taking a toll on his abilities or his escapability in the pocket. In fact, he cited making creative plays as part of his job description.

“If somebody gets beat, my job is to help them out once in a while and [make a play],” Romo said. “You don’t want to make a living at that. But, at the same time, part of my job is to do that. And they are going to make me look better on other plays.”

But those “other plays” have been few and far between the past two weeks, when Dallas managed just one offensive touchdown against Tampa Bay and during a 27-7 loss to Seattle. Romo figures to do his fair share of freelancing, once again, against the Bears’ stellar pass rush.

In those scramble situations, Romo said he’s “always judging and balancing” his next move based on the circumstances at hand: score, down-and-distance, time remaining.

“You just learn over time what you can do with certain things,” Romo said.

And when things go awry, as they have the past two weeks, Romo has learned to be patient and avoid letting frustrations become public. Even if teammates sense he is masking his emotions.

“It’s not always going to go perfect back there,” Romo said. “But … just keep grinding away and you can do some things. We’re going to continue to get better. I feel very confident.”