Two of the planet's most dangerous strikers couldn't produce a goal between them.
Ronaldo rattled a 30-yard strike off the left post in the 11th minute for Portugal, but Ivory Coast otherwise created the better opportunities.
"It was a tight game, not many occasions to score," Ivory Coast coach Sven-Goran Eriksson said. "I thought if any team was going to win, it was we. We created some more chances than they did. I am very, very happy with the performance. If you think about discipline and organization, I think we were organized for all 90 minutes."
Drogba came on as a 66th-minute substitute for fellow Chelsea striker Salomon Kalou after FIFA cleared him to play with a cast on his right arm, which he broke in a warmup match against Japan on June 4.
He was ruled eligible only shortly before kickoff at Nelson Mandela Bay Stadium, and his entrance was greeted by huge cheers, with vuvuzelas drowning out the drums of Ivorian fans for the first time in the match.
Still, Eriksson watched his star forward move comfortably, largely untroubled by an injury that threatened to prevent him from taking part in the monthlong World Cup.
"I spoke to him after training yesterday evening and he said he preferred to be on the bench," Eriksson said. "He said 'Boss, if you need me, I am there.' I hoped we would not need him, but we wanted to win the game, so we did what we did."
Ivory Coast had another injury problem late in the match when Kolo Toure went down clutching his leg and signaled to the bench for help.
The central defender was examined behind the goal line for a couple of minutes and hobbled back into action, but needed repeated treatment to his left knee with just minutes left.
Ronaldo's best chance came with a long, swerving shot that evaded goalkeeper Boubacar Barry but bounced off the left post.
Drogba, sitting among the substitutes, reacted to the near miss by blowing out his cheeks and making the sign of the cross across his shoulders.
Guy-Roland Demel brought down Ronaldo with a sliding foul in the 21st minute and referee Jorge Larrionda gave them both yellow cards for exchanging words with each other. Demel turned away from the referee without complaint, but Ronaldo argued with the official, asking what he had done wrong.
"I did nothing and he gave me a yellow card," Ronaldo said. "I do not understand."
Ronaldo also tapped in from close range in the 72nd minute, but the referee had already blown his whistle for offside.
Portugal coach Carlos Queiroz blamed his team's failure to create clearer chances on a defensive opponent.
"The game was a just result given the chances Portugal had in the first half and Ivory Coast had in terms of the counter-attack," Queiroz said.
Source: AP News