Best, the 37-year-old Irish skipper, has been feeling the heat from critics back home who feel it may be a campaign too far for the veteran, with his performance in the 50-point hiding by England at Twickenham in the summer warm-up series attracting particular ire.
But 29-year-old Edinburgh hooker McInally claimed to be oblivious to any such doubts about a player he admires greatly.
“I’ve had the pleasure of playing against Rory a couple of times now. Off the pitch he’s very friendly but on the pitch he’s a fierce competitor. He has played for Ireland a number of times and I know it means a lot to him. I’ve got a lot of respect for him as a player. He’s very good around the park, good over ball, a good set-piece player.
“He’s a player I respect a lot and I’m looking forward to going head on with him tomorrow.
“I’ve not been aware of any of that criticism. We look at players, watch the footage. We watched him against England, Wales and Italy and the Six Nations before that. I think he’s an excellent player.”
Irish rugby legend Brian O'Driscoll said it was "crazy" that Best is not already heralded as one of Ireland's great captains.
The Ulsterman has skippered Ireland since 2016, steering Joe Schmidt's side to the 2018 Six Nations Grand Slam, their maiden two victories over New Zealand - and now to the top of the world rankings for the first time.
After that Twickenham thumping, Ireland hit back with home and away wins over Wales to go back to No 1.
O'Driscoll skippered Ireland from 2003 until 2012 but, despite all his personal successes, can only count the 2009 Grand Slam as a major captaincy coup.
And Ireland's most-capped player now insists it is time for 37-year-old Best to receive far greater adulation.
"Rory is an absolute champion player, and a stalwart of this team," O'Driscoll said.
"Whatever he brings as a player he brings huge assets as a leader, and a calm head in stressful environments.
"I'm sure we'll see more big performances before he hangs up his boots - hopefully in November and not October.
"The fact that he's not already being revered as one of Ireland's great leaders is crazy. And do you know what? He doesn't have to be the best player on the pitch.
"He can even be the 15th best starting player, he just needs to be the best hooker.
"And he needs to focus on getting his darts right, scrummaging well and being destructive and annoying in the loose as we know he's been over the last 10 years. His leadership will be massively important to the progress of this team.
“I've been incredibly impressed with his diplomacy skills. Even when he's felt he's been on the receiving end of a bad refereeing decision, it's the look he gives, more than throwing his toys out of the cot, that's what referees want.
"They know he's annoyed, they know he thinks they've got it wrong, but they accept the respect part that he doesn't berate them or have a go at them.
"That's why he's really influential to this team, and that's why Ireland have had such an incredible disciplinary record, because he talks to referees, respects what they are saying and tries to feed in information to them, and steps away when he's told to.
"And I think that level of captaincy has been completely underestimated."