Friday's scoreless draw left the two-legged play-off wide open but the Portuguese are confident they will make the most of home advantage after the Bilino Polje Stadium's swampy pitch stopped them converting their control of the match into a win.
"That wasn't grass, we played on a vegetable patch. It was very difficult and still we did well and created chances," Ronaldo said.
The world's most expensive player, who last week picked up his second Golden Boot award as Europe's top scorer, was the most dangerous player of the game but his finishing was hampered by the poor state of the pitch.
"We now have a second chance at home in front of our fans, with a good pitch and have all the conditions to ensure we win," he added. "We have to assume we are favourites and show our superiority - we are a better team."
Their hard-working opponents were 12 minutes away from securing a berth in next year's finals when they led France 1-0 in their final group match, but were sent to the playoffs after the hosts' late equaliser.
The Portuguese had a dismal start to their Euro 2012 campaign but coach Paulo Bento revived the team's hopes, earning five straight wins after he took over in September last year.
"All teams go through different cycles and tough moments but we had a good qualifying [campaign], we simply did not grab that one point in Denmark... now, I believe we will win," Ronaldo said.
"Maybe the Portuguese think we will be easier opponents on a better surface but we won't. The fact is that we are also looking forward to play on a quality pitch," Bosnia striker Edin Dzeko said.
His partner in attack, Vedad Ibisevic, a second half substitute in Zenica, added: "We are confident that the tie will go down to the wire, especially if we play like we did against France in Paris."
