Bell did not report to the Steelers' facility for Wednesday morning meetings and has not signed his $14.5 million franchise tag, setting the stage for James Conner to start Sunday at Cleveland.
"Football's the ultimate team sport. One guy doesn't make or break you," Roethlisberger said Wednesday. "So I'd like to say that the linemen are more important than any skill-position player, including myself, on this team. This offense is more than one guy."
Added veteran center Maurkice Pouncey: "Conner's ready. He's been here busting his butt. A football team ain't defined off one player. This is a team unit and that's how we play ball."
Conner will get first-team reps this week, and teammates have praised his development. In the preseason, Conner produced 100 rushing yards on 19 carries along with 64 receiving yards.
Agent Adisa Bakari, who represents Bell, told SiriusXM NFL Radio on Wednesday that his client will "get there when he's there" and still intends to make this the best statistical season of his career.
"You're Kevin Colbert, you're Mike Tomlin, and you possibly have a once-in-a-generation player for one more season. What would your plan be?" Bakari asked.
It was pointed out to Bakari that he said earlier this year that he would follow the same blueprint as he did last season, when he reported ahead of Week 1.
"If memory serves, I said Le'Veon had every intention to make this the best statistical season of his career," Bakari said. "That hasn't changed. That's his intention -- to make this the best statistical season of his career."
Bakari was asked a follow-up question, pointing out again that he said the plan would be the same, barring something exceptional.
Bakari replied: "Well, there you go. We had something exceptional occur."
The Steelers started the 2015 and 2016 seasons without Bell, who served suspensions totaling five games. During that stretch, the Steelers went 3-2 while averaging 25.8 points per game. DeAngelo Williams led the way with 462 yards and five touchdowns.
"We did pretty good then, too," Roethlisberger said. "James is a year better than he was last year at this time. So I think we're all excited for what he can bring to this offense and this team. We've got a lot of weapons. We'd like [Bell] out there, but we've got guys who can make plays for us."
Steelers lineman Ramon Foster made light of the situation on Twitter, playing off "Where's Waldo?"
Stevan Ridley and rookie Jaylen Samuels will serve as Conner's backups. The Steelers typically sit players who don't practice in full on Fridays, and Bell hasn't entered team headquarters in nearly eight months.
The team has stayed unified in its approach to Bell, saying it's focused on players who are in uniform, but will welcome back the All-Pro.
Bell is arguably the game's most productive running back. His average of 128.9 total yards per game is the highest clip for a player's first five seasons since the NFL-AFL merger in 1970.
Bell forfeits $852,941 for every week he misses. That money returns to the Steelers' salary cap.
"We know he's one of the best in the business and he helps each week," Roethlisberger said. "When he gets here, I hope he'll be ready to go."