However, the Saints boss accepts Keane's team-mate Marc-Antoine Fortune will be just as dangerous, having scored four goals in the previous two meetings between the teams this season.
"There were a lot of positives to be taken from the first game at Parkhead when we lost 5-2 but we never defended well enough and good players punished us," said McInnes.
"Now Celtic have even more quality with Robbie Keane.
"It's great for the SPL that we have managed to attract someone of his quality.
"For the last decade he has been one of the best half dozen strikers in England.
"He can do everything as a striker but it would be wrong to say we will just concentrate on him.
"Fortune has scored four against us and the challenge for us is to keep him out.
"But they also have other players who can change the game so from the first to the last minute we will be aware of the threat.
"We have lost five and four against Celtic which is horrendous but over the piece our defensive record is generally not too bad.
"In the home game I thought we had the beating of them at half-time when we were winning 1-0.
"But we went down to 10 men and it became too difficult for us to hold out.
"However, we can take confidence from the fact that we have managed to score in both games against them.
"I have played in teams where you are not sure where the next goal is coming from but we have the belief that we can score goals, which is a good feeling.
"So we have asked questions of Celtic before and I'm sure we can ask questions of them again."
McInnes, though, is having to contemplate the possibility of travelling to Glasgow without 12 players.
Martin Hardie, Kevin Rutkiewicz, Steven Anderson, Stuart McCaffrey, Graham Gartland, Murray Davidson, Andy Jackson, Peter MacDonald, Collin Samuel and Kevin Moon are all out through injury or illness while Steven Milne is doubtful.
In addition, on-loan striker Cillian Sheridan is not allowed to face his parent club, but Saints confirmed on their official website they have completed the signing until the end of the season of 19-year-old Josh Falkingham, who was with Leeds until the end of December, and he will be in the squad.
McInnes learned that 22-year-old Moon could be out until September with damaged a cruciate ligament, the injury sustained during Tuesday's win over Aberdeen.
He said: "It's a huge blow for Kevin.
"I was wanting to freshen the team up with the game against Falkirk coming up next week but we will have to ask the same boys again and physically, it will be tough.
"But nobody outside this dressing room expects us to do anything in these games.
"Away matches against the Old Firm are the toughest on the calendar.
"But we will be determined to go there and get a result and if we defend well I wouldn't put it past us doing so."
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