If Campbell plays top-four minutes, it will allow Blackhawks coach Joel Quenneville to play defenseman Trevor Van Riemsdyk on the third pair. Last season, van Riemsdyk often played on the second pair.
Quenneville can shuffle partners on the third pair, likely choosing between Michal Kempny, 25, who was signed from the Kontinental Hockey League on May 24, and veteran Michal Rozsival, 37, who signed a one-year contract June 30 to return for a fifth season.
The Blackhawks also have Erik Gustafsson and Viktor Svedberg, who each played in the NHL last season, plus prospects Ville Pokka and Gustav Forsling.
Bowman said he's not concerned with Campbell and Rozsival taking up roster spots that otherwise would be used to groom young defensemen.
"This is the major leagues, and you want to compete for your spot and you want to earn it," Bowman said. "I think you get into trouble when you start handing out jobs to young players. There's a process for these guys to establish themselves as NHL regulars. And until they do that, they're going to be facing competition. And I think that's a good thing."